A study of the word rebuke, as it is translated in the NKJV of the Bible, is interesting and beneficial, especially as it relates to the New Testament. There are three words in the Greek language that are translated rebuke in the New Testament, each with different shades of meanings. They are: epitima?, elegch?, and epipl?ss?. A look at each of the three in turn are rather enlightening.
Let’s start out with epitima?. It is defined by Thayer, “to tax with fault, rate, chide, rebuke, reprove, censure severely…to admonish or charge severely… to charge one with wrong.”
Consider the following passages which use the term:
“Preach the word! Be ready in season and out of season. Convince, rebuke, exhort, with all longsuffering and teaching” (2 Timothy 4:2).
“Take heed to yourselves. If your brother sins against you, rebuke him; and if he repents, forgive him” (Luke 17:3).
“He [Christ, speaking about his suffering and death] spoke this word openly. Then Peter took Him aside and began to rebuke Him” (Mark 8:32).
“And some of the Pharisees called to Him from the crowd, ‘Teacher, rebuke Your disciples’” (Luke 19:39).
“Yet Michael the archangel, in contending with the devil, when he disputed about the body of Moses, dared not bring against him a reviling accusation, but said, “The Lord rebuke you!” (Jude 9).
As you note in Jude 9, this kind of rebuke is harsh. Something that even Michael the archangel was hesitant to proclaim about Satan himself. It is the work of the preacher to, sometimes in his preaching, censure severely, to clearly charge those who are in error with wrong, to attribute to them the fault that they have committed. But, it is a serious thing that should not be done lightly. In the cases of Peter rebuking Jesus, and the Pharisees charging Jesus to rebuke His disciples, they were both in the wrong. This was not surprising with the Pharisees for they were characterized as critical (cf. Matthew 23:1-5; Luke 18:11-12). Such rebuke often is less about the one receiving the admonition, and more about the critical nature of the one doing the rebuking, as in Matthew 7:1-5. Such ought not to be so.
A second, more reasoned word translated rebuke is the New Testament is elegch?. It is defined by Thayer: “to find fault with, correct.” Consider the following passages:
“This testimony [that Cretans are always liars, evil beasts, lazy gluttons] is true. Therefore rebuke them sharply, that they may be sound in the faith” (Titus 1:13).
[Paul’s instructions to Titus as an evangelist] “Speak these things, exhort, and rebuke with all authority. Let no one despise you” (Titus 2:15).
“As many as I love, I rebuke and chasten. Therefore be zealous and repent” (Revelation 3:19).
It is the work of an evangelist, to clearly and in a straightforward way, indicate fault. Jesus Himself did so to the church in Laodicea, writing, “I know your works, that you are neither cold nor hot. I could wish you were cold or hot. So then, because you are lukewarm, and neither cold nor hot, I will vomit you out of My mouth” (Revelation 3:15-16). As individual Christians we have the responsibility to do the same, for example, when someone sins against us (cf. Matthew 18:15-17). Such rebuke is not inappropriate because the pointing out of sin can “save a soul from death and cover a multitude of sins” (James 5:20).
This is why Paul told Timothy In 1 Timothy 5:20, “Those who are sinning rebuke in the presence of all, that the rest also may fear.” The rebuke of the sinner, used in this sense may bring repentance, but most certainly is beneficial to others as well (cf. 1 Corinthians 5:5-6).
But, that brings us to our final point — a seeming contradiction between verse 20, and verse 1-2 of 1 Timothy 5. We have already explained verse 20. Consider verses 1-2:
“Do not rebuke an older man, but exhort him as a father, younger men as brothers, older women as mothers, younger women as sisters, with all purity” (1 Timothy 5:1-2).
So, before telling Timothy to rebuke those who are sinning, he says do not rebuke an older man, older woman, younger man, younger woman. No there is no contradiction here, only a failure in the English to sufficiently translate the Greek. These are two different Greek Words. In verses 1 –2 the word is epipl?ss?, defined by Thayer, “to chastise with words, to chide, upbraid, rebuke”.
It is never appropriate to treat other Christians in this way. To chide them, to upbraid them. Our purpose is to save our wandering brethren, to show our love for them, not to deride them or treat them as enemies. “And if anyone does not obey our word in this epistle, note that person and do not keep company with him, that he may be ashamed. Yet do not count him as an enemy, but admonish him as a brother” (2 Thessalonians 3:14-10).
We are family. No rebuke or chastening should be done a way that disregards the love we have for each other.