Question: where in the bible does it say thou shalt not judge?
Answer: Bible Gateway Matthew 7 :: NIV. "Do not judge, or you too will be judged. For in the same way you judge others, you will be judged, and with the measure you use, it will be measured to you. "Why do you look at the speck of sawdust in your brother's eye and pay no attention to the plank in your own eye?