Someone once said that sitting in church doesn’t make you a Christian any more than sitting in a garage makes you a car. The apostle John would agree with that sentiment. His first epistle, the book of First John, is devoted to helping God’s people identify truth and discern genuine spirituality. As with his gospel account, John tells us exactly why he wrote this first letter: “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, and that you may continue to believe in the name of the Son of God” (1 John 5:13).

The purpose of First John is so we might say with confidence, “I know that I have eternal life.” It is not a matter of opinion but fact. God wants us to know with certainty that we have eternal life. In the pages of this epistle, we find five tests by which anyone can evaluate whether they are a Christian.

1. The Faith Test (1 John 5:1)

“Whoever believes that Jesus is the Christ is born of God.” John’s first test requires us to believe that Jesus is the Messiah of God. You can’t be a Christian without faith—but not just any faith. You must believe that Jesus of Nazareth is the promised Son of God. We don’t become Christians by praising, worshiping, serving, or teaching. We only become Christians by believing.

We don’t become Christians by praising, worshiping, serving, or teaching. We only become Christians by believing.

In 1 John 4:1-3, John explains what it means to believe that Jesus is the Christ: “Every spirit that confesses that Jesus Christ has come in the flesh is of God” (verse 2).

At the time of John’s writing, a heresy called Gnosticism was sweeping through the Middle East. It was not unlike the New Age movement of our day—a mystical approach to spirituality. John was writing to counteract the teachings of Gnosticism—to set in order the truth about knowing God. In verse two of chapter four, John highlights five essential things for a Christian to know and believe about Christ.

• Authentic faith believes in the pre-existence of Christ: “Jesus Christ has come in the flesh” (1 John 4:2). John does not say that Jesus began in the flesh, but that He came in the flesh, having pre-existed in spirit. His existence did not begin when He was born in Bethlehem. He arrived in Bethlehem having existed already. That was His pre-existence.
• Authentic faith believes in the incarnation of Christ: He came “in the flesh.” Although Jesus existed long before He became Mary’s Son, He became flesh by incarnating Himself in a human body. He was God walking around in a body. The Gnostics did not believe in incarnation. They believed Jesus became the Christ at His baptism. John refutes their error by stating that Jesus Christ existed before Bethlehem, that when He came to Bethlehem, He was born in the flesh.
• Authentic faith believes in the deity of Christ: Beyond being a human Messiah or the Messiah of the Old Testament, Jesus is the Son of God. He pre-existed His birth, was born as God in the flesh, and is the divine Son of God. He is the Deity, the Messiah, the One prophesied in the Old Testament.
• Authentic faith believes in the humanity of Christ. He was not only divine, but He was also fully human—the God-Man. Christ’s baptism did not transform His status from humanity to divinity. He was entirely human and entirely divine from the moment of His birth.
• Authentic faith believes in the eternity of Christ. Before Christ came in the flesh, He existed outside of earth’s space and time boundaries. He lived eternally before coming to Bethlehem in the flesh, and He lives eternally today. He came “in the flesh” and went to the cross to pay the penalty for our sin. Christ is the only one who could die for our sin and give us the gift of eternal life with Him.

Before Christ came in the flesh, He existed outside of earth’s space and time boundaries. He lived eternally before coming to Bethlehem in the flesh, and He lives eternally today.

We do not have to understand the mysteries of the God-Man’s incarnation to believe these things as Christians. First John 5:12 says, “He who does not have the Son of God does not have life.” We must have Jesus—believe He is the Son of God—to pass the faith test.

2. The Life Test (1 John 2:29)

Christians practice righteousness (1 John 2:29; 3:7, 10). Numerous times in First John, the apostle contrasts what people say with what they do. It’s easy to say something, but the reality is whether we do what we say. If we talk about righteousness without living a righteous life, we are not Christians. While we don’t become Christians by doing good works, we will choose to do good works once we are Christians. I have often had people tell me how their lives changed dramatically—they gave up an unholy habit or lifestyle—when they became Christians. That is evidence of the new life that belongs to every Christian.

Ephesians 2:8-10 provides the necessary framework. Many people are familiar with verses 8-9 that say we are saved by grace. But verse 10 continues, saying we are created “for good works, which God prepared beforehand that we should walk in them.” Those good works are the life test—the evidence that we have indeed been born of God (2 Corinthians 9:8; Titus 2:14; 3:5, 8; James 2:18). The Christian is not saved by works but for works. How we live is part of the evidence of what we believe.

The Christian is not saved by works but for works.

3. The Love Test (1 John 4:7)

There is a progression of truth regarding love in chapter four of 1 John:

• verse 7: “Love is of God.”
• verse 8: “God is love.”
• verses 9-10: “This is love… that He loved us and sent His Son to be the propitiation for our sins.”
• verse 19: “We love Him because He first loved us.”

See the sequence? Love is from God; God is love; God showed His love by sending Jesus into the world; He loved us, so we can love Him and others. If God had not first loved us, we would have no way of knowing how to love.

Verse 11 gives the ultimate point of progression: “Beloved, if God so loved us, we also ought to love one another.” Anyone who claims to be a Christian but doesn’t love their Christian brothers and sisters has a problem of inconsistency. Granted, not everyone in the world, or even in the Body of Christ, is easy to love. However, God loves us when we are not easy to love, and we are to love others as God has loved us.

When we find ourselves supernaturally able to love others the way God loves us, we provide evidence that we are born of God to ourselves and others. We have passed John’s love test. That love is the love God puts in our hearts for our family members—members, that is, of the family of God. Just as we love the members of our families, even though it’s not always easy, we do it because of our family bond. And the connection that all Christians have—all who are truly born of God—is that they love one another the way God has loved them. Because God is love, and He demonstrated His love by sending Jesus Christ to die for us, we can love one another if we have partaken of His love by believing in Christ.

The connection that all Christians have—all who are truly born of God—is that they love one another the way God has loved them.

So the next time you struggle to love a person who is not easy to love, prove to yourself that you are born of God by loving that person by faith.

4. The Growth Test (1 John 5:4)

The growth test is one of overcoming the world: “Whatever is born of God overcomes the world. And this is the victory that has overcome the world—our faith.” If we are born of God, we develop a spirit, an inner conviction and an ability, to begin rising above the pressures and temptations of the world system in which we live. Over time, every Christian should look back on things that once created personal struggles and conflicts, which are no longer. That is evidence of an overcoming spirit.

Second Corinthians 5:17 says that old things are passing away. They don’t immediately die the day you become a Christian, but they begin to pass away. The war against the world, the flesh, and the devil does not cease, but as you overcome, you win more battles than you lose. If sin is constantly defeating you, you have reason to ask whether you are, indeed, born of God. As we walk with the Lord, we should experience more and more victories in our Christian life.

If the One who is in us is greater than the one who is in the world (1 John 4:4), then we ought to be overcoming! This is a test for all who claim to be Christians—who believe they are born of God.

The longer I walk with the Lord, the more I grow convinced that overcoming the world is more about falling in love with Jesus than about focusing on resisting the evils of this world.

The longer I walk with the Lord, the more I grow convinced that overcoming the world is more about falling in love with Jesus than about focusing on resisting the evils of this world. When we contemplate what Christ has done for us, we find ourselves not wanting to displease Him by giving in to the world. Our attitude changes from, “I’m going to try not to do such-and-such,” to “I can do all things through Christ who strengthens me.” A person born of God focuses on Christ, not the world; as a result, they overcome the world.

5. The Sin Test

“We know that whoever is born of God does not sin; but he who has been born of God keeps himself, and the wicked one does not touch him.” Those truly born of God cease to live lives characterized by sin. This verse doesn’t mean that Christians never sin, but it does mean that we don’t immerse ourselves in sinful patterns. We belong to God, not Satan, and our life demonstrates that fact.

Many Christians have puzzled over this verse and others (1 John 3:6, 9, 10). “I still find myself sinning,” they say. “Does this mean I am not born of God?” If this were true, there would be no Christians on earth! Only Jesus has lived a perfectly sinless life. First John 3:4 contains the key to understanding 1 John 5:18. “Whoever commits sin also commits lawlessness, and sin is lawlessness”—and “lawlessness” is the transgression of the Law.

John is talking about sin as evidence of contempt for God’s Law—utter disregard for and rebellion against God’s authority as the moral ruler of the world. Anyone who consciously and intentionally violates God’s will cannot pass the sin test. John distinguishes the Christian who sins unintentionally and is sorry for that sin from the person who sins intentionally and is not repentant. The latter person is not born of God.

Anyone who consciously and intentionally violates God’s will cannot pass the sin test.

In these verses, John uses present tense verbs to talk about sin. This treatment assumes an ongoing, continual action. Christians do not make sin a routine practice. We may sin occasionally, but it is not a constant reality, a defining characteristic. A Christian can indeed choose to backslide and sin willingly, but a genuine believer will be miserable in that condition. Anyone who says they’re a Christian and who is not repentant when they sin fails to pass John’s final test.

Evaluating Your Test Results

John’s approach is simple: Either you know God and your life reveals that relationship, or you don’t. He did not want Christians to believe they could live in a manner inconsistent with truth, light, and especially love. For that reason, John’s first epistle is a powerful antidote to careless theology in our modern era. Knowing that Christians find reasons not to love one another, abstain from worldly temptations, and walk by light and truth, John gives a firm-but-loving directive for the Church.

How did you do on John’s five tests? If you failed all, I encourage you to seek the Lord and examine whether you are indeed His, a person genuinely born of God. If you failed on one or more, ask the Lord for insight into those areas of your life so they will align with your profession of faith. And if you passed all five, give God thanks for His grace at work in your life—grace whereby He first loved you so that you might love Him in return.