20 If anyone claims, "I love God," and hates his brother, he is a liar; for he who does not love his brother whom he has seen, how is it possible for him to love God whom he has not seen?
1 John 4:20 Cross References - CAB
1 Peter 1:8
8 Whom not having seen, you love, in whom now not seeing, but believing, you rejoice with inexpressible joy and glorified,
1 John 1:6
6 If we claim that we have fellowship with Him, and we are walking in the darkness, we are lying, and are not practicing the truth.
1 John 2:4
4 He who says, "I have come to know Him," and does not keep His commandments, is a liar, and the truth is not in him.
1 John 2:9
9 He who says that he is in the light, and hates his brother, is in darkness until now.
1 John 2:11
11 But he who hates his brother is in darkness and walks in darkness, and does not know where he is going, because the darkness has blinded his eyes.
1 John 3:17
17 But whoever has this world's goods, and sees his brother having need, and shuts off his compassion towards him, how does the love of God abide in him?
1 John 4:12
12 No one has ever seen God. If we love one another, God abides in us, and His love has been perfected in us.