1 Corinthians 4:21
21. with a rod, or in love—The Greek preposition is used in both clauses; must I come IN displeasure to exercise the rod, or IN love, and the Spirit of meekness (Isa 11:4; 2Co 13:3)?
1 Corinthians 5:5
5. Besides excommunication (of which the Corinthians themselves had the power), Paul delegates here to the Corinthian Church his own special power as an apostle, of inflicting corporeal disease or death in punishment for sin ("to deliver to Satan such an one," that is, so heinous a sinner). For instances of this power, see Ac 5:1-11; 13:11; 1Ti 1:20. As Satan receives power at times to try the godly, as Job (Job 2:4-7) and Paul (2Co 12:7; compare also as to Peter, Lu 22:31), much more the ungodly. Satan, the "accuser of the brethren" (Re 12:10) and the "adversary" (1Pe 5:8), demands the sinner for punishment on account of sin (Zec 3:1). When God lets Satan have his way, He is said to "deliver the sinner unto Satan" (compare Ps 109:6). Here it is not finally; but for the affliction of the body with disease, and even death (1Co 11:30, 32), so as to destroy fleshly lust. He does not say, "for the destruction of the body," for it shall share in redemption (Ro 8:23); but of the corrupt "flesh" which "cannot inherit the kingdom of God," and the lusts of which had prompted this offender to incest (Ro 7:5; 8:9, 10). The "destruction of the flesh" answers to "mortify the deeds of the body" (Ro 8:13), only that the latter is done by one's self, the former is effected by chastisement from God (compare 1Pe 4:6):
the spirit . . . saved—the spiritual part of man, in the believer the organ of the Holy Spirit. Temporary affliction often leads to permanent salvation (Ps 83:16).1 Corinthians 5:13
13. put away from among yourselves that wicked—Sentence of excommunication in language taken from De 24:7.
2 Corinthians 10:6
6. Translate, "Having ourselves (that is, being) in readiness to exact punishment for all disobedience," &c. We have this in store for the disobedient: it will be brought into action in due time.
when your obedience, &c.—He charitably assumes that most of the Corinthian Church will act obediently; therefore he says "YOUR obedience." But perhaps some will act otherwise; in order, therefore, to give all an opportunity of joining the obedient, he will not prematurely exact punishment, but wait until the full number of those gathered out to Christ has been "completed," and the remainder have been proved incorrigible. He had acted already so at Corinth (Ac 18:6-11; compare Ex 32:34; Mt 13:28-30).