Do not judge, or you too will be judged. For in the same way you judge others, you will be judged, and with the measure you use, it will be measured to you. Why do you look at the speck of sawdust in your brother’s eye and pay no attention to the plank in your own eye? Matthew 7:1-3
Jesus is cautioning us to not judge others in a hypocritical way. He is telling us to take the log out of our own eye so that we can help the other person take the speck out of his.
Just as believers are not to condemn others, we are not to ignore sin. If a believer sees another believer sinning, he is instructed to confront the person in a respectful and loving way. Matthew 18:15-17 The ultimate goal of confronting the person is to bring repentance and reconciliation. Let all that you do be done in love. 1 Corinthians 16:14