1 John 4:20

If anyone says, "I love God," and hates his brother, he is a liar; for he who does not love his brother whom he has seen cannot love God whom he has not seen.

1 John 2:4

Whoever says "I know him" but does not keep his commandments is a liar, and the truth is not in him,

1 John 2:9

Whoever says he is in the light and hates his brother is still in darkness.

1 John 3:17

But if anyone has the world's goods and sees his brother in need, yet closes his heart against him, how does God's love abide in him?

1 John 4:12

No one has ever seen God; if we love one another, God abides in us and his love is perfected in us.

1 John 2:11

But whoever hates his brother is in the darkness and walks in the darkness, and does not know where he is going, because the darkness has blinded his eyes.

1 Peter 1:8

Though you have not seen him, you love him. Though you do not now see him, you believe in him and rejoice with joy that is inexpressible and filled with glory,

1 John 1:6

If we say we have fellowship with him while we walk in darkness, we lie and do not practice the truth.

Treasury of Scripture Knowledge

Summary

If a man say, I love God, and hateth his brother, he is a liar: for he that loveth not his brother whom he hath seen, how can he love God whom he hath not seen?

Bible References

A man

1 John 2:4
Whoever says "I know him" but does not keep his commandments is a liar, and the truth is not in him,
1 John 3:17
But if anyone has the world's goods and sees his brother in need, yet closes his heart against him, how does God's love abide in him?

Not

1 John 4:12
No one has ever seen God; if we love one another, God abides in us and his love is perfected in us.

General references

Matthew 22:40
On these two commandments depend all the Law and the Prophets."
Matthew 25:42
For I was hungry and you gave me no food, I was thirsty and you gave me no drink,
John 13:35
By this all people will know that you are my disciples, if you have love for one another."
John 14:15
"If you love me, you will keep my commandments.
Hebrews 13:1
Let brotherly love continue.

The Holy Bible, English Standard Version® copyright © 2001 by Crossway Bibles, a publishing ministry of Good News Publishers.