How Do We Know If We're A Child of God?

Many of you know what the theme of First John is: It’s assurance. John wants us to know we have eternal life. He doesn’t want it to be a guessing game, or a, “I sure hope so kind of thing.” 1st John 5:13 clearly stated his purpose in writing this book, “These things I have written to you who believe in the name of the Son of God, that you may know that you have eternal life.”

So that we may know, John has given us a series of tests we can take. If we pass the tests, we can have assurance. But, if we fail, we’d better figure out why. We just may not be saved. We may have sadly deceived ourselves. At the very least, we aren’t doing so good living the Christian life.

One of these tests is found in 1st John 3:7-8, “Little children, let no one deceive you. He who practices righteousness is righteous, just as He is righteous. He who sins is of the devil, for the devil has sinned from the beginning. For this purpose the Son of God was manifested, that He might destroy the works of the devil.”

This test is talking about bearing a family resemblance: We are either a child of God or a child of the devil, there’s no other alternative. If we do righteousness, we are acting like our heavenly father. We are bearing his image. That’s evidence that we are His. If we sin, we’re acting like our father, the devil. We are bearing his image. That’s evidence that we are his. You can tell whose you are simply by looking at your actions. Is righteousness a characteristic of your life, or is sin?

But, before we talk about that, let’s define our terms. 1st John 3:4 actually defines sin: “Whoever commits sin also commits lawlessness, and sin is lawlessness.”

This is even clearer in the old King James: “Whosoever committeth sin transgresseth also the law: for sin is the transgression of the law.

Sure, there are other definitions in Scripture, but this one is the most basic - the most fundamental. What is sin? Sin is anything that is contrary to the law of God. It’s a nice, neat definition

But, wait a minute, this says law. We’re not under the Mosaic Law anymore are we? Of course not, but that doesn’t make us lawless. Look at 1st Corinthians 9:20-21, “And to the Jews I became as a Jew, that I might win Jews; to those who are under the law (The Jews who were under the Mosaic Law), as under the law (He adhered to the Mosaic law while with them so as not to offend them), that I might win those who are under the law; to those who are without law (The Gentiles who were never given the law), as without law (not being without law toward God (He was never lawless), but under law toward Christ (the moral teachings), that I might win those who are without law.”

Now look at James 1:25, “But he who looks into (what?) the perfect law of liberty and continues in it (New Testament believers), and is not a forgetful hearer but a doer of the work, this one will be blessed in what he does.”

Do you see this? We are not lawless people in the New Testament. We are not bound by the Law of Moses. That’s been set aside. We don’t have to sacrifice the animals anymore, since Christ made the one perfect sacrifice. We don’t have to follow the Jewish calendar of festivals, or their dietary laws. Not anymore.

But we are certainly not lawless. We are ruled by the Moral Law of Christ - the expressed will of Christ outlined throughout the pages of the New Testament.
And even more, it is written on our hearts. 2nd Corinthians 3:3 says: “Written not with ink but by the Spirit of the living God, not on tablets of stone but on tablets of flesh, that is, of the heart.”

So, what, then, is a sinner? A sinner is someone who is insubordinate to the will of God. It’s doing what we want instead of what God wants. Do you follow this?

A little girl was once asked in a Sunday School class, “What is sin?” She responded, “I think sin is anything you like to do.” She wasn’t too far from the truth.

You see, our problem is spelled out in Isaiah 53:6: “All we like sheep have gone astray. We have turned everyone to his own way.”

That’s it: We demand to have our own way, not God’s way. From the baby screaming in the crib, to the rebellious teen sneaking out at night, to the wayward spouse cheating on his mate, it’s always the same. The problem is the BIG “I.” “ I want my way, I’m my own man . Nobody tells me what to do, not my parents, not the authorities, not even God!” And we scream it out in our arrogance and rebellion.

Lawlessness, our rebellion against God, causes us to break speeding laws, cheat on our taxes, loaf on our employer’s time, to walk all over people on our way up the corporate ladder, to lie, covet, envy, and the list could go on and on and on.

Is there an answer? John gives us one in 1st John 3:5 – “And you know that He (Jesus) was manifested to take away our sins, and in Him there is no sin.”

There’s the answer - the answer is Jesus. This verse tells us Jesus came to earth with a mission. He appeared on earth (was manifested) in the flesh for a purpose, and that purpose was “to take away our sins.” Isn’t that exactly what John the Baptist said about Jesus? John 1:29 – “Behold, the Lamb of God who takes away the sin of the world.” Praise God for Jesus.