This is a tricky question because it does not specify what we are talking about. Certain things should be judged, like food. You should judge if it is suitable for eating. Eating rotten food is not good. Interiorly, we should judge what we say before we say it to fit the circumstances we are in.
When we speak of judging, though, we commonly mean judging others. So, are we supposed to judge others? No. Jesus said, “Stop judging, that you may not be judged. For as you judge, so will you be judged, and the measure with which you measure will be measured out to you.” – [Matthew 7:1-2] We do not judge so that we might not be judged the same way. Judging others is, as I have heard it, above our paygrade.
Well, Christians are commonly thought to be judgmental. Are these just bad Christians? In some cases, but Christians are thought to be judgmental for other reasons, too. We are supposed to be careful of what we do and, in doing so, we judge our actions.
Many times judging actions is construed as judging others. Someone who steals has acted improperly and judging the action of stealing has nothing to do with judging the person who stole. If we were able to judge the person, we would do so prematurely. They are on a journey and God will judge them when their journey on Earth ends.
Sometimes, we are thought to be judging others when we do nothing. Our mere presence and faith reminds others of what they are doing. Their conscience begins to judge them. There is a judgment going on, just not one from us. And so it is with the Church. The Catholic Church’s existence enlivens consciences and makes people feel judged. They are right, but they fail to realize who is doing the judging in this case.