Damocles,
Because you are not a Christian, you do not understand that we have a relationship with God, including personal revelation. I know what is wrong because God tells me what is wrong, and I know the will of God because I seek it. The God of the Bible is a knowable God.
USCitizen,
Your interpretation is incorrect, as Jesus commanded, Judge not according to the appearance, but judge righteous judgment. What Jesus does condemn is hypocritical judgment. For instance, the Pharisees who would judge a person for a particular sin, while committing that sin themselves. This is the essence of hypocrisy. Paul summarizes this in Romans chapter two, verse one of which says, Therefore thou art inexcusable, O man, whosoever thou art that judgest: for wherein thou judgest another, thou condemnest thyself; for thou that judgest doest the same things.
Consistency with John 7:24 requires the interpretation above to be the correct one.
Most of the theological seminaries are groveling in darkness, and know nothing of God. They are blind men leading the blind.