It is commonly asserted that Christians have no right to judge others, especially in a religious context. And, the verse that is often quoted is Matthew 7:1, “Judge not, that you be not judged.” 
Oh, but look at the context! Is Jesus really saying, “Don’t ever judge someone else”?
Jesus teaches for us to “first remove the plank” from our own eyes, “and then you will see clearly to remove the speck from your brother’s eye” (7:5). With the right attitude and right motive, it is ok to judge his speck. Jesus teaches, “Do not give what is holy to the dogs” or “swine” (7:6). How would we recognize “dogs” or “swine” without making any judgment? Jesus teaches, “Beware of false prophets” (7:15), but how would I know they are false prophets? “You will know them by their fruits,” whether they are “a good tree” or “a bad tree” (7:16-20).
When one puts Matthew 7:1 into its context, it is obvious that Jesus is not teaching that it is always wrong to judge. The key to proper judgment is two-fold: the right spirit (humility and agape love) and the right standard (“the measure” [v. 2] of God’s Word [John 7:24).