1 John 2:3-11  New Revised Standard Version Updated Edition

³ Now by this we know that we have come to know him, if we obey his commandments. ⁴ Whoever says, “I have come to know him,” but does not obey his commandments is a liar, and in such a person the truth does not exist; ⁵ but whoever obeys his word, truly in this person the love of God has reached perfection. By this we know that we are in him:^{(A) 6} whoever says, “I abide in him,” ought to walk in the same way as he walked.^(B)

A New Commandment

⁷ Beloved, I am writing you no new commandment but an old commandment that you have had from the beginning; the old commandment is the word that you have heard. ⁸ Yet I am writing you a new commandment that is true in him and in you, because^[a] the darkness is passing away and the true light is already shining.^{(C) 9} Whoever says, “I am in the light,” while hating a brother or sister, is still in the darkness.^{(D) 10} Whoever loves a brother or sister abides in the light, and in such a person^[b] there is no cause for stumbling. ¹¹ But whoever hates a brother or sister is in the darkness, walks in the darkness, and does not know the way to go, because the darkness has brought on blindness.^(E)