Child of God, Don't Let Sin Move In

Introduction

In this sermon on 1 John 2:29-3:10, Mélanie Ehrismann continues the series on John's first letter and walks you through a demanding text: the test of righteousness. To Christians shaken by false teaching, John holds together two truths that seem to sit in tension: you are truly a child of God, and that identity changes how you live. It's an invitation to gaze at the Father's love, to take sin seriously, and to refuse to let it move in and settle down.

Sermon outline

1. Gazing at the Father's love: you are truly a child of God

• John is writing to Christians shaken by teaching that contradicts the apostles' message and muddies the gospel.
• Throughout the letter, he runs several tests to gauge the authenticity of faith. Today's is the test of righteousness.
• Before anything else, John marvels: "Behold, how great a love the Father has bestowed on us, that we should be called children of God! And we are."
• This identity is a fact, whatever anyone else may think. It's the starting point for everything that follows.

2. The hope that purifies: we will be like him

• We are already children of God, but what we will become has not yet been fully revealed.
• When Christ appears, we will see him as he is, and we will become like him. That's the whole of God's plan: to make us like his Son.
• "Everyone who has this hope set on him purifies himself, even as he is pure." Reaching toward that end already purifies you now.
• This process connects with 2 Corinthians 3:18: as we gaze at the Lord's glory, we are being transformed into his image, from glory to glory.

3. Understanding the seriousness of sin

• John defines sin in verse 4: sin is rejecting God's law, disobeying him.
• It isn't a character flaw, and it isn't just an "oops, my mistake." It's an act of rebellion against God's will.
• In John's day, some people downplayed the seriousness of sin. Today we still hear that "it's already settled at the cross, no need to dwell on it."
• Failing to name the seriousness of sin greatly weakens the power of grace.

4. Sin and the Christian: incompatible

• Sin comes from the devil, who has been sinning from the beginning.
• The Son of God appeared precisely to take away sins and to destroy the devil's works. That's why Jesus died.
• To say sin isn't such a big deal is to say Jesus died for practically nothing.
• There are only two groups: those who do the works of God and those who do the works of the devil. John draws a hard line, leaving no comfortable third option.

5. Holding the tension: two ditches to avoid

• The first ditch: relentless perfectionism, trying to earn the right to be loved and to be called a child of God through your own effort.
• The answer: "If we confess our sins, he is faithful and righteous to forgive us the sins and to cleanse us from all unrighteousness" (1 John 1:9).
• The second ditch: accepting sin as a roommate, telling yourself "that's just how I am, I can't change."
• The answer: no, that isn't who you are. You are a child of God. Stop being friendly with that sin.

6. For the summer: God doesn't take vacations

• The shift in rhythm that summer brings is a chance to return to the heart of the gospel and to a relationship with the Father that bears fruit.
• God goes on vacation with you, wherever you're headed.
• In every situation, the question to ask is: what would Jesus do?
• The message closes with a reading from Galatians 5: "Walk by the Spirit, and you won't fulfill the lust of the flesh."

Key takeaways

• You are truly a child of God. It isn't a nice image, it's a fact, whatever the world may think.
• Your life reflects who you are. Our actions say who we are.
• Sin is an act of rebellion against God, not a minor slip. Taking it seriously means measuring the true power of grace.
• Jesus came to take away your sins and destroy the devil's works. His death was not symbolic.
• Be dissatisfied with sin's presence in your life. Refuse it. You are saved by grace, transformed by grace, and you will be glorified by grace.

Personal application

1. Take a moment to stop and reflect: what does it truly mean for you to "be a child of God"? Is it a reality that reaches you, or just an idea?
2. What do your actions say about who you are? Are they consistent with your identity as a child of the Father?
3. Is there a sin in your life you've grown too friendly with, a "roommate" who's been settled in for a while? Name it before God.
4. Are you more drawn toward perfectionism (earning love) or resignation ("that's just how I am")? How does the cross speak into that tendency?
5. This summer, in whatever situations you find yourself in, how will you simply ask: what would Jesus do?

Scriptures cited

• 1 John 2:29-3:10 (main text)
• 1 John 1:8-9
• 2 Corinthians 3:18
• Galatians 5:16-25

Frequently asked questions

Can a Christian keep sinning?

John holds two truths side by side. On one hand, if we say we have no sin, we deceive ourselves (1 John 1:8). On the other, whoever is born of God cannot keep making sin his way of life (1 John 3:9). A Christian still sins at times, but he can no longer settle into a habit of sin as if nothing were wrong. The answer is never to deny sin, but to always confess it, and to refuse to let it become normal.

What is sin according to 1 John 3?

John defines sin in verse 4: sin is rejecting God's law. It isn't a minor slip or a character flaw. It's an act of rebellion against God's will. To downplay the seriousness of sin is to downplay the power of grace.

Why did Jesus come, according to 1 John 3?

John gives two reasons. Jesus appeared to take away sins (v. 5) and to destroy the devil's works (v. 8). That's why Jesus died. To treat sin as if it weren't serious is to say Jesus died for practically nothing.