What does your criticism of others say about YOU?

It all starts with “me”, as in “my mind.”
The buck stops here.
In daily life, that means that whatever the mind says in judgment about others can be turned around to expose the nature of the mind. So if my mind judges you and says you are stupid, and that is turned around…it will reveal a “stupid” mind, using judgments to feel better about itself! Or if the mind says that someone is physically ugly, a turnaround shows a very “ugly” mind willing to put down someone for their physical features.
The turnaround produces revelations of the true nature of the mind. And seeing this again and again supports the understanding to NOT TAKE THE MIND TOO SERIOUSLY! This is a major step in breaking down the barriers to the heart.