1 John 2:3-10 CSB
This is how we know that we know him: if we keep his commands. The one who says, “I have come to know him,” and yet doesn’t keep his commands, is a liar, and the truth is not in him. But whoever keeps his word, truly in him the love of God is made complete. This is how we know we are in him: The one who says he remains in him should walk just as he walked.
Dear friends, I am not writing you a new command but an old command that you have had from the beginning. The old command is the word you have heard. Yet I am writing you a new command, which is true in him and in you, because the darkness is passing away and the true light is already shining. The one who says he is in the light but hates his brother or sister is in the darkness until now. The one who loves his brother or sister remains in the light, and there is no cause for stumbling in him.
CSB: Christian Standard Bible