There is a tension in scripture on the use of the word "judge."
For example, John 7:24, and many other similar passages say things
like, "Stop judging by mere appearances, but instead judge correctly.”
While in contrast, Romans 14:4 says, "Who are you to judge someone else’s servant? To
their own master, servants stand or fall. And they will stand, for the
Lord is able to make them stand... You, then, why do you judge your
brother or sister? Or why do you treat them with contempt? For we will
all stand before God’s judgment seat."
yet, 1 Corinthians 6:2 says: "Do you not know that the Lord’s people will judge
the world? And if you are to judge the world, are you not competent to
judge trivial cases?"
all seems like it could be a problem. Taking a look at the full context of each of those passages helps, and I think the Apostle James offers further assistance. Judging rightly is closely related to
teaching, admonishing, and loving others well, and James has this to say
about teachers: "Not many of you should become teachers (which
inevitably involves making judgements), because you
know that we who teach will be judged more strictly. [Remember] we all
stumble in many ways." James 3.
And Paul says this: "Do nothing
out of selfish ambition or vain conceit. Rather, in humility value
others above yourselves, not looking to your own interests but each of
you to the interests of the others." Philippians 2:1-4
In my judgement, many Christians are like this blogger, who writes at length on why it is ok to judge others, without looking at the tension in scripture, or talking about how to do so well. (He lists nearly every passage that says judge, but never looks at Romans 14.)
Exercising discernment, care, concern, teaching, or judgement without humility is an effort doomed to fail, and too often, that is exactly what happens. (For me in particular.) That is one of the reasons non-Christians, and former Christians, and Christians who often don't identify as Christians, and our culture in general disdains judgement so much; they rarely experience it combined with humility and graciousness.