When Jesus was asked if a woman should be condemned for a sin she had committed, he replied, "He that is without sin among you, let him cast the first stone." Hearing this, the accusers examined their own consciences. One by one, they walked away.
No one can know all the underlying, mitigating reasons influencing the behavior of others - and therefore cannot judge them fairly or accurately. In the very act of judging, we close the door to having an open heart - and, in ways, become like the person we judge.
We should always be attentive to assisting others on their paths to understanding, rather than being an impediment.
Philosophers and scholars have examined this principle for thousands of years. The meaning is clear: we are to be aware of our own spiritual shortcomings and lessons, spend our time and effort in healing them.
Judge not thy neighbor until you are in his place. - Judaism
Do not judge your neighbor - Buddhism
All religions teach that we are to love one another, that we are to seek out our own shortcomings before we presume to condemn the faults of others... Who are we to judge? - Baha'i
Judge not, and you will not be judged; condemn not, and you will not be condemned; forgive, and you will be forgiven. - Christianity