Charles Ellicott Commentary 1 Corinthians 5:7

"Purge out the old leaven, that ye may be a new lump, even as ye are unleavened. For our passover also hath been sacrificed, [even] Christ:" — 1 Corinthians 5:7 (ASV)

Purge out therefore the old leaven.—It is not the offending man who is spoken of here, but it is the spirit in the Church which tolerated the evil, and which is to be purged out of their midst, so that they may actually become (a new lump) as they are by profession (unleavened).

Christ our passover is sacrificed for us.—Better, Christ our passover is slain; “for us” is not in the best manuscripts. The word translated “sacrifice” is generally used in the New Testament simply in the sense of “slaying” or “killing” (Matthew 22:4; John 10:10; Acts 10:1; Acts 10:13; Acts 11:7); and in similar expressions regarding our Lord (Revelation 5:6; Revelation 5:12), the word is “wounded.”