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Fight for Your Faith

Lesson 13 · Quarter 3 2026 · 09/13/2026 · 18 min read

By Equipe Marcas Editora

The video has automatic English dubbing. If you hear Portuguese, open the player settings (⚙) → Audio track → English.

Golden Text

“Beloved, although I made every effort to write to you about the salvation we share, I felt it necessary to write and urge you to contend earnestly for the faith entrusted once for all to the saints.” (Jude 3, BSB) · Read in the Bible

Jude sat down to write about salvation and changed the subject in the middle of his own sentence: people had crept into the church, turning the grace of God into a license to live any way they wanted. The lesson closes the quarter with the easiest verb to misunderstand in the New Testament — contending for the faith — and spends a good part of the time saying what it does not mean: it is not permission to be hostile to an atheist classmate, a relative of another religion, a Christian from another church, or a stranger on the internet. Jude's target was inside the house, and the tactic he teaches works from the inside out: building yourself up in the faith, praying in the Holy Spirit, keeping yourself in the love of God, and having mercy on those who doubt. And it ends where Jude ended: in the One who is able to keep us from stumbling.

There is a specific hour when doubt arrives. It is almost never in the middle of the worship service. It is late at night, with your phone in your hand, when you should already be asleep and the next video starts playing on its own.

The guy seems smart. He speaks calmly, doesn't yell, doesn't insult anyone. And he says, as naturally as can be, that the Bible is a poorly stitched-together ancient book, that Jesus was just a cool teacher, and that religion is the way scared people found to sleep better at night. In the comments, three thousand people agreeing.

You lock your phone. But something stays open.

It is for people in your situation that the letter we are going to study today exists. It has twenty-five verses — it fits on a single page — and it is the last lesson of this quarter. After three months of reading the New Testament letters, we finish with the toughest one of all.

And before opening the Bible, a warning about how to read this lesson, because it is the easiest one in the quarter to misuse.

The title is "Fight for Your Faith." It is not "fight with whoever disagrees with you." Nothing in this lesson authorizes you to mistreat the atheist classmate in your room, cut off your cousin who became a spiritist, humiliate your neighbor from another church, or start a fight in the comment section. If you leave here wanting to shut someone up, the lesson didn't work. Write that down right now, because we are going to come back to this point carefully.

In this lesson we are going to understand why Jude changed the subject in the middle of his own sentence, separate what "contending for the faith" is from what it is not, and discover the four verbs the letter gives to those who want to remain standing.

1. The letter that changed the subject

The writer introduces himself with a modesty that stands out: "Jude, a servant of Jesus Christ and a brother of James, To those who are called, loved by God the Father, and kept in Jesus Christ:" (Jude 1).

Notice what he did not say. Jude was the brother of the Lord, according to Matthew 13:55 and Mark 6:3 — he grew up in the same house, ate at the same table, knew Jesus before any crowd knew Him. He held in his hand the best badge in early Christianity. And he chose to introduce himself as a servant.

That is not false humility; it is doctrine. Before the cross there is no privileged family connection. What counts is belonging to Christ — and Jude, who had already been a brother according to the flesh, preferred to be a brother by faith.

Now the most interesting part. Read the Golden Text slowly:

"Beloved, although I made every effort to write to you about the salvation we share, I felt it necessary to write and urge you to contend earnestly for the faith entrusted once for all to the saints." (Jude 3)

Did you catch what happened in there? Jude changed the subject in the middle of the sentence. He had a plan: to write a letter about salvation, about what all Christians share in common. It must have been a pleasant letter to read. And, halfway through, he stopped and said: I can't. There is something more urgent.

You know when you open your phone to send a message and, before you finish typing, a piece of news arrives that changes everything? It is more or less like that. Urgency ran over the script.

Ω In the original — Greek. The verb translated here as "contend earnestly" is epagōnízesthai (ἐπαγωνίζεσθαι). At its heart is the word agṓn, which was the name for an athletic competition — the contest, the struggle in the stadium. From that same root comes a word you use in English without realizing it: agony. In other words, Jude did not choose a verb of warfare with a sword; he chose a verb of sustained effort, of the athlete who trains, who suffers, who does not quit the race halfway through. It is not the language of someone attacking another person. It is the language of someone holding on until the end.

And there is another small phrase that changes everything: that it was entrusted once for all to the saints.

Two ideas inside that.

First: it was entrusted. The Christian faith was not invented by us, was not voted on in an assembly, is not the product of whoever had the best idea. It was received. That is liberating, if you stop to think about it: you don't need to put together your own version of Christianity, with the parts you like and without the ones that bother you. It already came ready. Your job is not to create — it is to guard.

Second: once for all. The expression carries the idea of something done once and for all, with no need to be repeated. Version 2.0 is not coming out. A new revelation is not coming ten years from now to correct the cross.

And it is precisely because it is a received treasure that it can be stolen, watered down, or counterfeited. No one counterfeits what is worthless.

2. Who Jude's target was (and who it was not)

Here is the point that decides whether this lesson will do you good or harm.

Jude writes to Christians about a problem that was inside the church:

"For certain men have crept in among you unnoticed — ungodly ones who were designated long ago for condemnation. They turn the grace of our God into a license for immorality, and they deny our only Master and Lord, Jesus Christ." (Jude 4)

Read again the idea that they slipped in secretly. They did not walk through the front door announcing: "hello, I have come to destroy your faith." They came in sideways, without a name tag, speaking the language of the house. They were in the worship service. They probably helped out at the church's love feasts (Jude 12).

And Jude gives two objective signs to recognize them. Keep both, because they have not changed in two thousand years:

1) They turn the grace of God into a license for immorality. In other words: they take the most beautiful thing in the Gospel — the forgiveness we do not deserve and cannot pay for — and turn it into an excuse to live however they please. The reasoning is always the same: "God forgives anyway, so it doesn't matter." That is not grace. Grace is what sets you free from sin, not what gives you a license for it.

2) They deny Christ as Lord. Notice the verb: it is not "they deny that Jesus existed." It is denying that He is in charge. You can say you love Jesus, post Bible verses, cry while singing in worship — and still remain the sole authority over your own life.

Jude spends the middle of the letter describing the damage this kind of person causes, with images anyone can understand: waterless clouds that promise rain and wet nothing; fruitless trees; wild waves of the sea, foaming up their own shame, and wandering stars (Jude 13). A wandering star is something that looks like a guide and isn't — you follow it thinking you are being led somewhere, and you aren't.

And he closes the list with the heaviest diagnosis: "These are the ones who cause divisions, who are worldly and devoid of the Spirit." (Jude 19).

🔬 Our reading. Now the most important warning in this article, and it needs to be spelled out plainly: this list is not an identification chart for you to apply to the people in your church. Jude was a recognized leader, writing publicly to entire congregations about a problem the leadership already knew about. He was not teaching teenagers to investigate brothers and sisters. If you finish this lesson with the name of someone from your class, your worship team, or your leadership in your head, you have turned the text inside out. The mirror here points inward. And if you see something truly wrong — the kind that hurts people or puts someone at risk —, there is only one path: tell a trusted adult right away, your father, mother, pastor, or teacher, privately. No screenshots, no group chats, no audience. The adult handles it; the teenager speaks up.

What "contending for the faith" is not

Since the letter uses strong language, it is worth stating out loud what it does not authorize. None of these things is contending for the faith:

  • It is not being hostile to those who do not believe. Your atheist classmate is not the infiltrator of Jude 4. He is a person for whom Christ died.
  • It is not cutting off a relative of another religion. The aunt who turned to another faith is still your aunt, and Christian love has no exception clause.
  • It is not attacking a Christian from another church. Disagreement among brothers and sisters is not heresy, and the internet is full of people confusing the two.
  • It is not winning an argument. Whoever wins the debate and loses the person has defended nothing; they just made themselves feel good.
  • It is not fighting in the comments. Not a single soul is saved in the comment section. Only egos are fed.

The Christian tone is not in doubt in the Bible. It is written:

"But in your hearts sanctify Christ as Lord. Always be prepared to give a defense to everyone who asks you the reason for the hope that is in you. But respond with gentleness and respect," (1 Peter 3:15)

Three things there. Prepared — it takes work, it requires study. Answering everyone who asks — not running over people who didn't ask. With gentleness and respect — without arrogance and without mockery.

And Paul adds the finishing touch: "Act wisely toward outsiders, redeeming the time. Let your speech always be gracious, seasoned with salt, so that you may know how to answer everyone." (Colossians 4:5-6). Salt gives flavor and preserves; in excess, it ruins the food. Some people think they are being firm when they are just being rude.

There is also the matter of the right timing: "A word fitly spoken is like apples of gold in settings of silver." (Proverbs 25:11). The very same true statement, spoken at the wrong time, hurts instead of helping.

3. The four verbs of those who stand firm

If defending the faith is not attacking anyone, what is it? Jude answers, and the answer works entirely from the inside out. Four verbs, two verses:

"But you, beloved, by building yourselves up in your most holy faith and praying in the Holy Spirit, keep yourselves in the love of God as you await the mercy of our Lord Jesus Christ to bring you eternal life." (Jude 20-21)

Build yourselves up. To build up is to construct, brick by brick, and no one builds overnight. It means truly studying the Bible, and not just hearing about it. There is a huge difference between knowing that the Bible says something about a subject and knowing where it says it. Whoever knows where to look does not panic when the question comes. And an honest comparison is worth making: have you spent more time this week learning a play in a game, a dance routine, or a school subject than understanding what you believe?

Pray in the Holy Spirit. Here is the center of our Pentecostal faith, and it is good that it appears right in a lesson about standing firm. It is not dressed-up prayer, with pretty words to impress whoever is listening. It is dependent prayer — the kind born when you admit you cannot handle it on your own. The Holy Spirit is not an ornament of doctrine; He is the One who empowers the believer to remain. Jude puts the two things together on purpose: study and prayer, head and knees. Separated, both go sour. Head alone becomes the pride of knowing; emotion alone becomes a faith that evaporates at the first hard question.

Keep yourselves in the love of God. Hold on to this verb, because we will come back to it at the end. Notice that it is a command, given to you.

Wait for the mercy of Christ. Eyes on the end of the road. Whoever is not waiting for anything up ahead gets tired back here.

God keeps and the believer keeps himself

There is a pair of verses in this letter that must be read together, because separated they produce two opposite lies.

On one side, Jude opens by saying that Christians are kept for Jesus Christ (Jude 1) and closes by worshiping the One who is able to keep you from stumbling (Jude 24). The keeping belongs to God. It is real, it is strong, and it does not depend on your Monday-morning mood.

On the other side, in the middle of the same letter, stands the command to keep yourselves in the love of God (Jude 21).

Read the three together and the math adds up. God keeps, and the believer keeps himself. A command is only given to someone who can obey or disobey — no one commands a river to flow downhill. If it were impossible to be lost, the entire letter would have no reason to exist: Jude would not write twenty-five verses of warning to people facing zero risk.

So do not fall into either of the two ditches. The first is thinking that, since God keeps you, it doesn't matter how you live — that was归 exactly what the men of Jude 4 were teaching. The second is thinking that everything depends on your own effort, and living in fear that one bad day will erase everything. Neither a leash nor a tightrope. Grace empowers; you cooperate. Every day, the same way any living relationship is maintained.

4. What about those who are in doubt?

After all that firmness, the letter makes a turn that many people do not expect. Jude could have ended by ordering the doors shut. He does the opposite:

"And indeed, have mercy on those who doubt; save others by snatching them from the fire; and to still others show mercy tempered with fear, hating even the clothing stained by the flesh." (Jude 22-23)

The first word about the doubter is compassion. Not "expel," not "expose," not "ridicule." Show mercy.

That tears down the angry reading of this lesson once and for all. The person who is wavering in the faith — the friend who stopped going to church, the classmate who started saying none of this makes sense, you yourself going through a rough patch — is not an enemy to be defeated. They are people to be rescued. Snatching them from the fire is the image of a firefighter, not a judge. Someone who runs into a fire to pull a person out does not preach a sermon at the door.

And notice the fine balance of the verse: mercy toward the person, with no fondness for the error. Jude commands us to love the one who is falling and to hate what is bringing them down. It is perfectly possible to remain friends with someone who changed their mind without adopting their idea. In fact, that is what Christian maturity looks like in practice.

A direct consequence for your week: doubt is not sin. If you have had a question stuck in your throat for months and never told anyone because it would look "unspiritual," the Bible itself has just given you permission. Hidden doubt rots; doubt brought to God and to someone mature becomes a root.

Christ in the Lesson

Now comes the question that decides everything: who, after all, is holding on to whom?

Because if you have read this lesson up to here and your conclusion was "so I have to try harder," you understood the opposite of what Jude wrote. Notice how he ends the letter. After twenty-three verses of stern warning, he does not close by saying "good luck, hang in there." He closes like this:

"Now to Him who is able to keep you from stumbling and to present you unblemished in His glorious presence, with great joy — to the only God our Savior be glory, majesty, dominion, and authority through Jesus Christ our Lord before all time, and now, and for all eternity. Amen." (Jude 24-25)

Stop at two expressions.

Able to keep you from stumbling. It does not say "able to pick you up after you fall" — aunque He does that too. It says to keep you from stumbling. His care begins before the fall.

To present you blameless. That is the most surprising word in the letter. Blameless means having nothing of which to be accused. And if you know your own week, you know that word does not describe you. That is why it is not talking about what you managed to be — it is talking about what Christ did for you on the cross. Whoever enters blameless before the glory of God does not enter by their own résumé; they enter under the blood of Jesus.

And now put that together with the sentence from the Golden Text. The faith was entrusted to the saints — but it cost a prior surrender. Before any doctrine was entrusted to the Church, the Son was delivered up to the cross. There is no Christian faith to defend if the tomb is not empty.

That is why "fighting for your faith" has never meant fighting alone. You contend because Someone already fought first and won. Paul, at the end of his life, looked back and summed it up in three short clauses: "I have fought the good fight, I have finished the race, I have kept the faith." (2 Timothy 4:7). Notice that he did not say "I created the faith." He kept what he had received. That is exactly what is being asked of you.

And that is the end of the quarter. Three months of letters, and the final word is not about how much you can endure. It is about who holds on to you.

Practical Application

Trade complaining time for learning time. The next time a video shakes your faith, instead of replying in the comments, write the question down and go look for the answer. Fifteen minutes of searching are worth more than an hour of arguing.

Study one thing a week. It doesn't have to be a course. One chapter read carefully, one question brought to your teacher, one note in the margin of your Bible. Building up is brick by brick.

Pray before answering, not after fighting. Praying in the Holy Spirit comes before any defense of the faith in Jude's order — and that is no accident.

Check your tone. If your last conversation about faith ended with someone feeling humiliated, the problem was not the doctrine. Gentleness and respect (1 Peter 3:15) are not optional.

Treat the friend who is doubting the way Jude commanded. Stay a friend. Keep inviting them. Do not turn them into a project and do not announce to anyone that they have "backslidden." Showing mercy is quieter than it looks.

And what you must not do: do not police the internet, do not put together call-out posts, do not confront any leader. If something truly wrong bothers you, talk privately with your parents or with your church leadership. If it is serious, tell a trusted adult right away.

Closing Prayer

Lord Jesus, thank You because the faith I have was not invented by me — it was entrusted to me, and it cost You the cross. Forgive me for the times when I wanted to win an argument more than reach a person, and for the times when I stayed silent out of sheer laziness to know what I believe. Teach me to study Your Word with a real hunger. Fill me with Your Holy Spirit, because on my own I cannot stand firm. Guard my tone: may I be firm without being cruel, and gentle without being weak. Have mercy on my friends who are in doubt — and on me, on the days when the doubter is me. And thank You, Lord, because in the end the One who keeps me from stumbling is not me: it is You. In Your name, amen.

Soli Deo Gloria — Scripture governs; everything else, on its knees.

Frequently asked questions about this lesson

Does contending for the faith mean I have to argue with people who do not believe?+

No, and that is the most common misreading of this verse. Notice whom Jude was writing to and about whom: he writes to Christians, about people who had already crept into the church and were distorting the Gospel from within (Jude 4). It is not a letter about an unbelieving neighbor. Besides, the Bible is very specific about the tone: "But in your hearts sanctify Christ as Lord. Always be prepared to give a defense to everyone who asks you the reason for the hope that is in you. But respond with gentleness and respect," (1 Peter 3:15). Notice that it means answering those who ask, not attacking those who did not ask. And Paul adds: "Let your speech always be gracious, seasoned with salt, so that you may know how to answer everyone." (Colossians 4:6). Anyone who wins an argument and loses the person has not defended the faith at all.

Why does Jude quote a book that is not in the Bible?+

That is an honest question and deserves a direct answer. Jude speaks of Enoch prophesying (Jude 14) and of the dispute over the body of Moses (Jude 9), and both appear in ancient Jewish writings that are not part of Scripture — 1 Enoch and the Assumption of Moses. Those books are not the Bible, and our church does not receive them as Scripture. So what did Jude do? Exactly what Paul did twice: in Athens, Paul quoted pagan poets to speak of God — noting that even some of their own poets had said so (Acts 17:28) — and to a Cretan he quoted a Cretan poet (Titus 1:12). No one ever concluded from this that Greek poetry became Scripture. Quoting a true statement does not turn the whole book into the Word of God. Under the inspiration of the Holy Spirit, Jude used an image his readers knew and validated that specific truth — that God is coming to judge — not the book.

If the faith was delivered once for all and is already complete, why do so many people disagree about what the Bible says?+

Because disagreement is not a sign that the text is confusing; often it is a sign that we are the ones coming to it crookedly. Notice that Jude does not say 'discover the faith' or 'build the faith.' He says it was delivered — it already came ready, from the outside in, and our part is to keep it, not reinvent it. That, by the way, is the best news in this letter: you do not need to create your own version of Christianity, nor should you. About disagreeing: there is a difference between what is central and what is peripheral. The core — who Jesus is, what He did on the cross, how a person is saved — is clear, and the Church has believed it since the first century. It is precisely this core that the men in Jude's letter were attacking.

If God is able to keep me from stumbling (Jude 24), can I just live however I want and lose nothing?+

No, and Jude himself closes that door four verses earlier. In the very same letter in which he says that God is able to keep you, he gives a command to the believer: "keep yourselves in the love of God as you await the mercy of our Lord Jesus Christ to bring you eternal life." (Jude 21). A command is only given to someone who can obey or disobey. Both things are there together on purpose: God keeps, and the believer keeps himself. God's keeping is real, sufficient, and does not depend on your strength — but it is not a leash. That is why the entire letter is a warning: if it were impossible to go astray, there would be no reason to write. Grace enables you to remain; it does not remain in your place.

I have real doubts. Does that mean I am one of the false ones in the letter?+

No. And notice what Jude commands to be done specifically with those who are in doubt: "And indeed, have mercy on those who doubt;" (Jude 22). The command for the doubting is mercy, not expulsion. The people he denounces are not those who ask questions; they are those who taught that the grace of God is a license to live any way they wanted and denied the lordship of Christ (Jude 4). That is something else entirely. Honest doubt is often the beginning of a faith that will finally be your own and not borrowed from your parents. What doubt needs is a destination: take it to God and to someone mature, instead of leaving it spinning alone in your head late at night.

How do I know if a preacher I follow on the internet is a false teacher? Should I warn people?+

The letter gives two very objective signs, and neither of them has to do with style, clothes, or channel size: the person turns grace into an excuse to live without holiness, and takes away from Jesus His place as Lord (Jude 4). Those are the tests. Now, the second part of the question is the most important: no, going around calling people out is not your job, much less in a comment, group, or story. You are fifteen or sixteen years old and are not in charge of policing the internet — not even adults are. The path is different: unfollow them, and take your question to your pastor, your teacher, or your parents in private. If it is something serious that hurts someone or puts someone at risk, tell a trusted adult right away. The adult handles it; you report it.

Teens

Quarter 3