How you judge other people is the same judgment that will come back upon you. That is the reason God told us not to judge. God is the only one who can judge. Amplified Bible says in Matthew 7:1-2: (1) Do not judge and criticize and condemn others, so that you may not be judged and condemned yourselves. (2) For just as you judge and condemn others you will be judged and criticized and condemned and in accordance with the measure you (used to) deal out to others it will be dealt out again to you.
Read Psalm 1. What if God pulled back the curtain of your own life for all of us to see? Would you be ashamed of what you did? What happened in our youth is in the past. None of us is perfect. If you have been saved then these sins have been forgiven and forgotten, and under the blood of Jesus. Usually what you judge in other people you are doing it yourself. I would be afraid to judge anyone. You cannot go forward with your life as long as you are looking back to the past. Turn to Jesus. He loves you so much.