However, Paul warned against overreacting. The church should always treat the offender as a brother, not an enemy. We warn brothers, but we denounce and condemn enemies. The aim of all church discipline must be repentance followed by restoration. [1][source]
"The situation is different from that envisaged at Corinth, where "someone who is called a brother" (ean tis adelphos onomazomenos ...) lives and acts in such a way as to give the lie to his Christian profession; that person is to be treated as an unbeliever, with no entitlement to the privileges of Christian fellowship ( 1 Corinthians 5:11)." [2][source]
Context Summary
2 Thessalonians 3:6-18 - Separate Industrious Persevering
From his high expectations of the Advent, the Apostle turns to the prosaic commonplaces of daily toil. There was need for this, because the expectation of the speedy return of Christ was disarranging the ordinary course of life and duty. People were neglecting the common round of daily tasks, and idlers were imposing on Christian generosity. Against these the Apostle sets his own example of sitting far into the night at his tent-making. See 1 Thessalonians 2:9. The best attitude for those that look for their Lord is not in pressing their faces against the oriel window, to behold the chariot of their returning Master, but in plying their toil with deft hands and consecrated hearts.
Note that parting salutation, 2 Thessalonians 3:16, and let us believe that the God of peace is causing peace for us at all times and in all ways. Even storms are forwarding our boat to its haven, and we shall be borne in with the flood tide of His mercy. Every wind is a home wind to the child of God, setting in from the quarter of His love. Every messenger, however garbed, brings God's salutation and benediction [source]
Chapter Summary: 2 Thessalonians 3
1Paul craves their prayers for himself; 3testifies what confidence he has in them; 5makes request to God in their behalf; 6gives them various precepts, especially to shun idleness, and ill company; 16and then concludes with prayer and salutation
Greek Commentary for 2 Thessalonians 3:15
Not as an enemy [μη ως εχτρον] This is always the problem in such ostracism as discipline, however necessary it is at times. Few things in our churches are more difficult of wise execution than the discipline of erring members. The word εχτρος echthros is an adjective, hateful, from εχτος echthos hate. It can be passive, hated, as in Romans 11:28, but is usually active hostile, enemy, foe. [source]
Reverse Greek Commentary Search for 2 Thessalonians 3:15
Colossians 1:28We proclaim [καταγγελλομεν] Paul, Timothy and all like-minded preachers against the Gnostic depreciation of Christ. This verb originally (Xenophon) meant to denounce, but in N.T. it means to announce Admonishing (νουτετουντες nouthetountes). Old verb from νουτετης nouthetēs admonisher (from νουσ τιτημι nousδιδασκοντες tithēmi). See already Acts 20:31; 1 Thessalonians 5:12,1 Thessalonians 5:14; 2 Thessalonians 3:15, etc. Warning about practice and teaching (παντα αντρωπον didaskontes) about doctrine. Such teaching calls for “all wisdom” Every man Repeated three times. “In opposition to the doctrine of an intellectual exclusiveness taught by the false teachers” (Abbott). That we may present (ινα hina parastēsōmen). Final use of παριστημι hina and first aorist active subjunctive of τελειον paristēmi for which see note on Colossians 1:22, the final presentation to Christ. Perfect Spiritual adults in Christ, no longer babes in Christ (Hebrews 5:14), mature and ripened Christians (Colossians 4:12), the full-grown man in Christ (Ephesians 4:13). The relatively perfect (Philemon 3:15) will on that day of the presentation be fully developed as here (Colossians 4:12; Ephesians 4:13). The Gnostics used teleios of the one fully initiated into their mysteries and it is quite possible that Paul here has also a sidewise reference to their use of the term. [source]
Greek Commentary for 2 Thessalonians 3:15
This is always the problem in such ostracism as discipline, however necessary it is at times. Few things in our churches are more difficult of wise execution than the discipline of erring members. The word εχτρος echthros is an adjective, hateful, from εχτος echthos hate. It can be passive, hated, as in Romans 11:28, but is usually active hostile, enemy, foe. [source]
See on Acts 20:31, and see on Ephesians 6:4. [source]
Reverse Greek Commentary Search for 2 Thessalonians 3:15
Paul, Timothy and all like-minded preachers against the Gnostic depreciation of Christ. This verb originally (Xenophon) meant to denounce, but in N.T. it means to announce Admonishing (νουτετουντες nouthetountes). Old verb from νουτετης nouthetēs admonisher (from νουσ τιτημι nousδιδασκοντες tithēmi). See already Acts 20:31; 1 Thessalonians 5:12, 1 Thessalonians 5:14; 2 Thessalonians 3:15, etc. Warning about practice and teaching (παντα αντρωπον didaskontes) about doctrine. Such teaching calls for “all wisdom” Every man Repeated three times. “In opposition to the doctrine of an intellectual exclusiveness taught by the false teachers” (Abbott). That we may present (ινα hina parastēsōmen). Final use of παριστημι hina and first aorist active subjunctive of τελειον paristēmi for which see note on Colossians 1:22, the final presentation to Christ. Perfect Spiritual adults in Christ, no longer babes in Christ (Hebrews 5:14), mature and ripened Christians (Colossians 4:12), the full-grown man in Christ (Ephesians 4:13). The relatively perfect (Philemon 3:15) will on that day of the presentation be fully developed as here (Colossians 4:12; Ephesians 4:13). The Gnostics used teleios of the one fully initiated into their mysteries and it is quite possible that Paul here has also a sidewise reference to their use of the term. [source]
Old verb from νουτετης nouthetēs admonisher (from νουσ τιτημι nousδιδασκοντες tithēmi). See already Acts 20:31; 1 Thessalonians 5:12, 1 Thessalonians 5:14; 2 Thessalonians 3:15, etc. Warning about practice and teaching (παντα αντρωπον didaskontes) about doctrine. Such teaching calls for “all wisdom” [source]