1 John 2:2-5

He is the propitiation for our sins, and not for ours only but also for the sins of the whole world. And by this we know that we have come to know him, if we keep his commandments. Whoever says “I know him” but does not keep his commandments is a liar, and the truth is not in him, but whoever keeps his word, in him truly the love of God is perfected. By this we may know that we are in him