51 It is actually reported that there is sexual immorality among you, and such sexual immorality as is not even named among the Gentiles, that one has his father’s wife. 2 You are puffed up, and didn’t rather mourn, that he who had done this deed might be removed from among you. 3 For I most certainly, as being absent in body but present in spirit, have already, as though I were present, judged him who has done this thing. 4 In the name of our Lord Jesus Christ, you being gathered together, and my spirit, with the power of our Lord Jesus Christ, 5 are to deliver such a one to Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus. 6 Your boasting is not good. Don’t you know that a little yeast leavens the whole lump?
Matthew Henry's Commentary on 1 Corinthians 5:1-6
Commentary on 1 Corinthians 5:1-8
(Read 1 Corinthians 5:1-8)
The apostle notices a flagrant abuse, winked at by the Corinthians. Party spirit, and a false notion of Christian liberty, seem to have saved the offender from censure. Grievous indeed is it that crimes should sometimes be committed by professors of the gospel, of which even heathens would be ashamed. Spiritual pride and false doctrines tend to bring in, and to spread such scandals. How dreadful the effects of sin! The devil reigns where Christ does not. And a man is in his kingdom, and under his power, when not in Christ. The bad example of a man of influence is very mischievous; it spreads far and wide. Corrupt principles and examples, if not corrected, would hurt the whole church. Believers must have new hearts, and lead new lives. Their common conversation and religious deeds must be holy. So far is the sacrifice of Christ our Passover for us, from rendering personal and public holiness unnecessary, that it furnishes powerful reasons and motives for it. Without holiness we can neither live by faith in him, nor join in his ordinances with comfort and profit.