The Lord Jesus Christ forbids judging others:
“Judge not, that you be not judged” (Matt. 7:1)
“Judge not, and you shall not be judged. Condemn not, and you shall not be condemned. Forgive, and you will be forgiven” (Luke. 6:37)
Addressing these words to those who judge others while themselves full of an even greater sin:
“Or how can you say to your brother, ‘Let me remove the speck from your eye’; and look, a plank is in your own eye? Hypocrite! First remove the plank from your own eye, and then you will see clearly to remove the speck from your brother’s eye” (Matt. 7:4-5)
At the same time, He teaches to judge with righteous judgment:
“Do not judge according to appearance, but judge with righteous judgment” (John. 7:24)
“Therefore do not be unwise, but understand what the will of the Lord is” (Eph. 5:17)
“Yes, and why, even of yourselves, do you not judge what is right?” (Luke. 12:57)
The apostles speak of the necessity of judgment:
“For what have I to do with judging those also who are outside? Do you not judge those who are inside? But those who are outside God judges. Therefore ‘put away from yourselves the evil person’” (1 Cor. 5:12-13)
“Dare any of you, having a matter against another, go to law before the unrighteous, and not before the saints? Do you not know that the saints will judge the world? And if the world will be judged by you, are you unworthy to judge the smallest matters? <...> I say this to your shame. Is it so, that there is not a wise man among you, not even one, who will be able to judge between his brethren?” (1 Cor. 6:1-2,5)