When should a Christian try to correct another Christian?

This can be a delicate subject. It is wise to spend time in prayer
first, to check our motivation and ask for guidance. There are times
when Christians are called upon to "talk to" or try to correct a
fellow Christian. Assuming we are talking about a matter of sin in a
believers' life, our motive and intent should always be to bring about
repentance and restoration to the erring brother or sister in Christ.

First, our attitude is very important. "Be kind and tender to one
another. Forgive each other, just as God forgave you because of what
Christ has done" (Ephesians 4:32). It is then that we are more able to
"speak the truth in love" (Ephesians 4:15). In his epistle to the
Galatians, Paul had a similar warning about attitude: "Brothers, if
someone is caught in a sin, you who are spiritual should restore him
gently. But watch yourself, or you also may be tempted" (Galatians
6:1). Here we see that those who are "spiritual," meaning walking in
the Spirit in faith and obedience, should gently restore someone who
is in sin, being always aware of how easily we can all be tempted by
Satan who wants to ensnare everyone in his traps.

The Bible prescribes the procedure for confronting a sinning brother
or sister in an extensive passage on church discipline: "If your
brother sins against you, go and show him his fault, just between the
two of you. If he listens to you, you have won your brother over. But
if he will not listen, take one or two others along, so that 'every
matter may be established by the testimony of two or three witnesses.'
If he refuses to listen to them, tell it to the church; and if he
refuses to listen even to the church, treat him as you would a pagan
or a tax collector" (Matthew 18:15-17). Again, this is the procedure
for confronting a sinning brother, not someone whose behavior you feel
needs modifying in some way or someone who merely irritates or annoys
you.

On a different slant, one of the most often quoted scriptures is
"Judge not, lest ye be judged" (Matthew 7:1 KJV). Taken out of
context, the verse has been used to incorrectly justify never taking a
stand on anything that would require a judgment to be made. Rather,
the verse is referring to hypocritical, self-righteous, unfair kinds
of judgment, especially where the confronter is guilty of the same sin
as the one being confronted.

So, when should Christians talk to or try to correct a fellow
Christian? When we have talked to the Lord first, have an attitude of
submission and concern for the other person, and are committed to
following the procedures outlined in His Word for such a situation.