Is Les judging people when he teaches this passage?
The teacher is not judging people. He states he is not looking down his nose but simply showing what Scripture says, as God builds His case against all humanity—immoral, moral, and religious—concluding all are guilty and none does good, leading to Romans 3.
Les teaches that from this point until Romans 3, God is building His case like a prosecuting attorney against the whole human race. He categorizes humanity into three groups: the immoral (or amoral, destitute of any morality), the moral man or woman, and the religious individual. The conclusion is guilty for all three. Paul then comes to the tremendous conclusion in Romans 3: there is none that doeth good, none that doeth righteousness; all have become unprofitable. Les reminds his audience and classes that he is not looking down his nose and not judging; he is simply showing what the Scripture says. It is God building His case against all humanity, starting with the most obviously guilty—the immoral.