Paul tells the Corinthians to “Test yourselves to see if you are in the faith; examine yourselves” (II Corinthians 13:5). The Bible is very specific in describing what is required to be “in the faith.”
John says that if we really love God there will be four results of this love and it will show if we are in the faith.
First, we will know God and God will know us. “We know that we have come to know Him if we obey His commands” (1 John 2:3). This is a personal relationship with Christ established when we repent of our sins and trust Christ as our personal savior.
Second, John says if we really love God, we will obey him. “If anyone obeys His Word, God’s love is truly made complete in Him. This is how we know we are in Him” (1 John 2:5). Jesus said, “If you love me, you will keep my commandments” (John 14:15).
The third result of loving God is that we love the brethren. “Dear friends, since God so loved us, we ought also to love one another” (1 John 4:11). John repeats this over and over again. He says, “If someone says, ‘I love God,’ yet he hates his brother, he is a liar. For anyone who does not love his brother, whom he has seen cannot love God whom he has not seen” (1 John 4:20). If we love God, we will love each other.
John says the fourth result of loving God is that we will abide in him (1 John 4:15-16). Jesus said, “I am the vine; you are the branches. If a man remains in me and I in him, he will bear much fruit; apart from me you can do nothing” (John 15:5). We, as a branch, receive life from the vine, Jesus Christ. Apart from him we can do nothing.