How Do We Know Who Knows God?
Jesus came into the world but then left the world promising to come back. For two thousand years, people have claimed to be his followers, claiming to know God because they believe in Jesus. This is a big claim! Christians claim to know God by believing in someone none of us has ever seen before.
This is why many people see the Christian faith as irrational. But Christians aren’t the only ones who claim to know a God they can’t see. All religions make similar claims. So how do we know who really knows God?
In the letter we’re studying, First John, written toward the end of the first century by one of Jesus’ first followers John, we learn that those who truly know God believe certain things, love certain people, and live a certain way. They have specific beliefs about who Jesus is and what he did. They love other people who share these beliefs and they live in distinct ways.
The Moral Test
John gives us three “tests” (doctrinal, relational, moral) so that we can know who truly knows God. In our passage today, John comes back to the “moral test.” The kind of things he says in our passage could lead many to believe that Christianity is only about morals, about cleaning up our lives and looking good on the outside. But that would be to miss all the other things he says in the letter about Christians believing certain things and deeply loving people.
For John there’s a fundamental connection between knowing God and doing righteousness. Those who claim to know God will live a certain way. There are things they won’t do that everyone else is doing and things they will do that no one else is doing.
But their lifestyle isn’t conformed to their own moral preferences. They believe that there’s an objective standard of morality outside of themselves. Their goal is to live a life conformed to the life of Jesus. They know that the world says, “Be true to you,” but that Jesus says, “Be true to me.” That the world says, “Discover yourself,” but Jesus says, “Deny yourself.” That the world says, “Follow your heart,” but Jesus says, “Follow me.”
In other words, the Christian life is one that is radically devoted to Christ. But John is actually doing something more in our passage than just saying, “Live like Jesus.” He’s saying, “Jesus coming into the world to die for our sins and his coming back again is all the reason we need to live like him.” In other words, it’s not just straight command, though God has the right to do that. John’s argument is rather that Jesus’ first and second coming compel us to live lives that look like his. We don’t have to be told what to do because Jesus’ first and second coming is a stronger incentive to holiness than a sheer command.
That’s the main point of our passage today, First John 2:28-3:10, that Jesus’ first and second coming compel us to live like him. We’ll see how Jesus’ first coming compels holiness in 3:4-10, then how Jesus’ second coming compels holiness in 2:28-3:3.
Jesus’ First Coming Compels Holiness
First, Jesus’ first coming compels us to holiness (3:4-10). John’s argument in these verses is that Jesus’ first coming was to “take away sins,” so God’s people are those who put away sin (vv. 4-7). And then John says that this reveals whether we’re children of God or children of the devil (vv. 8-10).
Verse 5 says that “he (Jesus) appeared in order to take away sins.” How did he do that? 2:2 says that he was the “propitiation for our sins,” meaning that he absorbed the wrath of God toward sin in our place. Like a sponge, Jesus soaked up all of God’s displeasure toward us for sinning against him. Jesus drank every drop of God’s justice toward sinners. In 1:7, John says that Jesus’ blood “cleanses us from all sin.” Jesus’ blood washes the dirty stain of sin off our souls.
So when John says that “Jesus appeared in order to take away sins,” he means that through Jesus’ death, our sins can be forgiven and washed away. Like the hymn says, “My sin, oh the bliss of this glorious thought, my sin, not in part but the whole, is nailed to the cross, and I bear it no more.” The forgiveness of sin through the death of Jesus on the cross is the heart of Christianity (2:12). Without this beating heart, the whole thing dies.
Sinlessness of Jesus Means His Followers Don’t Tolerate Sin
But notice in our text how John uses the death of Christ for our sins to make a specific point. At the end of verse 5, John says, “And in him there is no sin.” Like the sacrificial animals in the Old Testament, Jesus had to be without blemish in order to be an acceptable sacrifice for sins.
However, John isn’t making that point. He’s bringing up Jesus’ sinlessness to make a more practical point. He’s saying that anyone who claims to know God yet lives in unrepentant sin can’t claim to know Jesus because Jesus is without sin. John’s point is that if Jesus was sinless then his followers won’t tolerate sin.
These verses seem to be implying that a sinless perfection is required to really prove that we know God, but that’s not what John is saying. In 2:1, he concedes that Christians can and do sin. And in 1:10 he says that if we say we haven’t sinned, we’re lying. So it’s better to understand these verses as saying something like, “If we live in sin, then our claims to live in God aren’t credible.” This was really relevant for these churches because the false teachers were claiming to know God but weren’t living righteously.
John’s overall point here is simple: Jesus came to take away our sin, therefore we must put away our sin. To put it another way, we can put away our sin because Christ was taken away our sin. The only sin that we can repent of is forgiven sin.
“Let God Do His Work, We Will See to Ours”
In May of 1780, the skies grew dark in New England and many people thought it was the Day of Judgment and that Jesus’ return was imminent. It turns out that the darkness was caused by forest fires in Canada. But the Connecticut State Legislature debated whether to continue its session because of the darkness as some assumed that their work was pointless if Jesus was coming back any moment. But one Senator said, “Let God do his work, we will see to ours. Bring in the candles.”
God has done the heavy lifting of removing the penalty and breaking the power of sin in our lives through Jesus’ death on the cross. Our job is to fight with all our might to remove the presence of sin. “Let God do his work, we will see to ours.” Jesus took away our sin so we can put away our sin.
This can sound overwhelming because we have so much sin to put away. You may think, “No, I’m actually doing pretty good,” but just take some time and start analyzing your motives, why you really do what you do, and you’ll see just how much the cancer of sin has spread in your life.
But others may be really struggling to see any progress in your life, and you feel like you’re not even a Christian because of your sins. It may help you if you compared how you feel about Jesus, the Bible, and the church today compared to how you felt about them last year, or five years ago, or thirty years ago. You may be farther along than you think.
John Newton said, “I’m not what I want to be or ought to be, but I’m not what I once was. By God’s grace, I am what I am.” If we’ve been washed clean by Jesus’ blood, our lives will start to look more and more like Jesus.
Destroying the Works of the Devil
Notice next that those who claim to know God but continue to consistently pursue sinful behavior means that they are “of the devil” (v. 8). They’re doing what the devil does, sinning. Genesis 1-4 shows us that “from the beginning” the devil has been trying to undo God’s work by keeping people from doing God’s will, that is, causing them to sin.
But John says that Jesus “appeared to destroy the works of the devil,” meaning that through his death for sin he destroyed the devil’s work because the devil’s work is to get us to sin.
John is saying that we must not be led astray by anyone who suggests that sin doesn’t matter. He says it must matter because Jesus died to destroy the devil’s work, which is to lead people to sin.
Thankfully, defeating sin isn’t something we’re left on our own to do. Holiness isn’t a matter of willpower. Notice the interesting word-picture John uses in verse 9. He says that believers have “God’s seed living in them.” Scholar Colin Kruse calls this “a most daring metaphor.” “Seed” is from the Greek word sperma. So John is saying that God’s “sperm” is in us.
This metaphor is related to what John means when he talks about believers being “born of God” earlier in the verse. Being “born of God” means being given new spiritual life by the will of God through the power of the Holy Spirit. We’re born of God by God, the Spirit. Thus, God’s “seed” living in us most naturally refers to God’s Spirit living in us (cf. 2:20).
So the Holy Spirit inside of us is why we can fight and kill sin. Without the Spirit, we would “keep on sinning” and live like the devil. But Jesus came to destroy the works of the devil, so those who know Jesus will also destroy the works of the devil in their lives by the power of the Spirit of Christ in them. The imparting of the life of God creates a life that looks like God’s.
Jesus’ first coming was to “take away sins,” so God’s people are those who put away sin, which reveals whether we’re children of God or children of the devil. Jesus’ first coming compels us to live like him.
Jesus’ Second Coming Compels Holiness
Next, Jesus’ second coming compels holiness (2:28-3:3). The main thing to see here is the connection between Jesus’ second “appearing” and our call to live holy lives.
In 2:28, John says that abiding in Christ prepares us for his return, and then in verse 29 he tells us that abiding in Christ means “practicing righteousness.”
What does John mean by “abiding in Christ”? In John 15, Jesus tells his disciples to “abide in his love” (v. 9), and then that obeying his commandments is what reveals that we’re abiding in his love (v. 10). Abiding results in obeying.
The Greatness of God’s Love
What does God’s love look like? 3:1-3 is a beautiful section on God’s love. It seems unrelated to the topic at hand, but the end of verse 3 shows us that John is still on the theme of the holiness of God’s people. Verse 1 says that the greatness of God’s love is seen in that he calls us his children. And we aren’t just “called” God’s children, we are God’s children, “and so we are.”
Then he says that being the children of God won’t gain us any respect with the world. If an unbelieving world full of people opposed to God didn’t recognize Jesus, then they won’t recognize us either.
Then in verse 2 he says that what we are now stands in contrast to what we will be later. We can’t fully comprehend what we’ll be later, but we do know that “when he appears we shall be like him.” Paul helps us understand what John means. He says in Philippians 3:21, “(The Lord Jesus Christ) will transform our lowly body to be like his glorious body, by the power that enables him to bring everything under his control.”
John says that the reason for this change is because “we shall see him (Jesus) as he is.” Paul again helps us understand John’s meaning. He says in Colossians 3:4, “When Christ who is your life appears, then you also will appear with him in glory.” When Jesus returns, we will see him in all his glory and just the sight of him will be enough to transform our lowly bodies into glorious and immortal new bodies.
Hope Creates Purity
But this reality is not John’s main point here. Verse 3 is his point. He says that everyone who has the hope of verse 2 will purify their lives. He’s saying that the hope of being like Jesus in the future expresses itself in a desire to be like him in the present. Hope creates purity.
Notice that Jesus’ purity is the goal, “purifies himself as he (Jesus) is pure.” Christians understand that we aren’t the ones who decide what’s pure and impure.
John says that our purity should be a reflection of Jesus’ purity. This begs the question for all of us to consider, do our lives reflect the purity of Jesus? Do our words and thoughts and actions and attitudes reflect his purity? Does what we watch, listen to, talk about, and enjoy as entertainment grow us in the purity of Jesus?
What we often do is say to ourselves, “Well I don’t do what that person does, or watch what they watch, or listen to what they listen to, so I’m doing okay.” But John says the standard is Jesus, not the person you like comparing yourself to. So it’s good to ask ourselves, “Would Jesus do what I do?” Or even better, “Would I do what I do, listen to what I listen to, watch what I watch if Jesus were sitting with me?” Our standard of purity is Jesus, not our friends or family, not social media, not the culture. If Jesus wouldn’t do it, then neither should we.
Paul said, “Since we have these promises, beloved, let us cleanse ourselves from every defilement of body and spirit, bringing holiness to completion in the fear of God” (2 Cor. 7:1). We have promises and hope, so we do all we can to wash our lives of anything impure, anything that we’d be ashamed of Jesus catching us doing.
One of the things that can happen in a church like ours with a high view of Scripture and a commitment to sound doctrine is that we would care more about doctrinal purity than moral purity. John says both are important. Paul tells Timothy to keep an eye on his life and doctrine. So we need to guard against being quick to be the theology police and slow to deal with secret sin. May we be just as passionate about sexual purity as we are about doctrinal precision.
Righteousness On Us Will Come Out of Us
For John there’s a fundamental connection between knowing God and doing righteousness. Those who claim to know God will live a certain way. There are things they won’t do that everyone else is doing and things they’ll do that no one else is doing.
John’s argument is that Jesus’ first and second coming compel us to live lives that look like his., that Jesus’ death for our sins and his glorious return are enough to compel us to live like him.
If Jesus has put his righteousness on us, then his righteousness will start to come out of us. Those who wear his righteous robes want to please the One who put them on.