>> “I read somewhere judge not lest you be judged.” <<
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You should have read the whole chapter; it commands that we must judge, but that we first clean up our own act.
I.e. we get the spiritual part straight. So then we can make a sensible judgment. One that we would declare would be right if we got it ourselves were the positions reversed. It is another expression of the Golden Rule.
I am going to try not to judge others until I clean up my own act, Unfortunately I probably will not be able to completely clean up my own act so the only judgment I should do to others is dealing with keeping my own act clean.