Let's say this judging and criticism is not valid; you're just nitpicking on somebody, you don't like their hair, or you don't like the shirt they're wearing. Let's deal with this level first: we're being judgmental and critical about something the other person is doing but it's not really a proper thing to be critical about. So we note it. The minute you are aware that you're doing something unbeneficial, note that you're doing it. Then try to have Compassion for yourself for having that negative mind state at that time. If the person might have a characteristic that's a bit odd, but it's not really something you should criticize then you could have Compassion for that other person, too, that they have that odd characteristic. So those are clear techniques. If you're trapped for a long time, besides having Compassion for yourself, you've got to learn how to forgive yourself. There is a forgiveness meditation in the Special Retreat teachings, but if you haven't learnt it yet, the Compassion/Lovingkindness techniques can deal with it.
Now on a different level, if we've been judgmental and critical about something which is clearly negative, that's good, that's really good, do it. You don't have to change that one. If you see somebody who's beating up our dog here, make the judgment. That person is not doing the right thing. Be critical of that person for beating up that dog, the dog doesn't deserve it. So, to be judgmental and critical when it's merited is fine. When it's not merited, then you've got to watch your mind.
So the other parts of these questions: Can we bend that energy to help us to reflect deeper? Of course. And also the technique we gave you last night, the D/D method, defusing and diffusing. If you get caught up in a big unmerited judgmental attack, if you're criticizing somebody here for doing something when they're not really doing anything wrong and you realize it, you can do a D/D Compassion/Lovingkindness meditation. Start with yourself, you got very critical this morning, that wasn't right, you created your own pain. Do the Compassion/Lovingkindness wish for yourself. Then consider somebody else, your age, your sex, somewhere in the world doing the same thing at that moment, somewhere there's a women this age, somewhere a man 10 years older, a women 10 years older and so on. So open it up, use it as a catalyst to reflect deeper.
What is the cause? If we're judgmental in an unmerited way, the cause is that we don't feel secure in ourselves. If we feel content, if we feel secure in ourselves, why should we worry about what other people are doing? If it's not really harmful, why worry? We won't put any attention to it, we see something that might be odd for somebody else, we may just easily open our heart, and have Compassion/Lovingkindness for them. So when we're content with ourselves, that's the opposite of being judgmental and critical in a negative way.