He means before you judge someone to harshly think about what might be happening in their life and think about how they might be having an even harder time then they could be giving you. Yes it is definitely illegal. This could help you get along with people because you could find out what’s going on in their life and find a way to help them instead of judging them harshly. I don’t do this but I am going to try and do this from now on so I get along better with other people. I think that doing this does help you get along better with other people even if you don’t realize it.