The relevant passages here are from Paul’s first letter to the believers in Corinth:
I have already pronounced judgment on the one who did such a thing. (1 Corinthians 5:3)
Therefore do not pronounce judgment before the time, before the Lord comes, who will bring to light the things now hidden in darkness and will disclose the purposes of the heart. Then each one will receive his commendation from God. (1 Corinthians 4:5)
It’s not just Paul. Jesus also says not to judge:
“Judge not, that you be not judged. 2 For with the judgment you pronounce you will be judged, and with the measure you use it will be measured to you.
But then he says to judge:
Do not judge by appearances, but judge with right judgment. (John 7:24)
This is a classic case of having to read in context. Trying to establish Bible teaching on the basis of individual verses without reference to their context is a bad but common practice.
If we read further in Paul’s letter to the believers in Corinth:
For what have I to do with judging outsiders? Is it not those inside the church whom you are to judge? God judges those outside. “Purge the evil person from among you.” (1 Corinthians 5:12-13)
Looking at all of the verses together, the overall teaching seems to be:
- don’t judge people’s motives (after all, we can’t possibly know what they are);
- don’t act as though you can judge whether someone will be in God’s kingdom or not (that’s not our job);
- don’t judge harshly (or God will deal with you in the same way);
- don’t judge unbelievers (they have not yet committed themselves to a godly life).
On the other hand, we have a responsibility to make judgments about what happens within the community of believers. In 1 Cor 5:3, Paul is talking about sexual immorality within the church and it is necessary then to make a judgement about what to do. Ignoring it (i.e., not judging) would be wrong — this is the problem that has led to the cover-up of sexual abuse within many churches.