Matthew 7:2

"Be careful," He says. "You are stepping into a minefield when you begin to judge your brother!" Because the dangers are hidden, minefields are especially deadly, and judging beyond our area of authority is just as dangerous. If we ignore the warning and continue pressing forward, judging beyond our authority will blow up in our faces, ripping us to shreds!

Why are we warned so strongly against judging others? In The Complete Word Study Dictionary, p. 892, Spiros Zodhiates writes, explaining the difference between the words krites and dikastes (both meaning "judge"):

Krites, as used of God (Hebrews 10:30; 12:23; James 4:12) involves the inherent power to discern the character of a person. Similarly it is an attribute of Christ in the same manner as it is an attribute of God (Acts 10:42; II Timothy 4:8; James 5:9). On the human level, a krites is one who makes a judgment as to the character and actions of others without receiving such appointment from someone [i.e. God did not give us the authority] whereas dikastes implies a responsibility attributed by society and others. Therefore dikastes is more of a forensic term, a judicial judge, while krites is one who uses his subjective criteria to evaluate others.

John W. Ritenbaugh
Judging Our Brothers