Now by this we may be sure that we know him, if we obey his commandments. 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; but whoever obeys his word, truly in this person the love of God has reached perfection. By this we may be sure that we are in him: whoever says, “I abide in him,” ought to walk just as he walked.
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. Yet I am writing you a new commandment that is true in him and in you, because the darkness is passing away and the true light is already shining. Whoever says, “I am in the light,” while hating a brother or sister, is still in the darkness. Whoever loves a brother or sister lives in the light, and in such a person there is no cause for stumbling. But whoever hates another believer is in the darkness, walks in the darkness, and does not know the way to go, because the darkness has brought on blindness.
Scripture passage from the New Revised Standard Version Bible: Catholic Edition, copyright 1989, 1993, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.