Test and prove what pleases the Lord.
These verses contain a caution against all manner of uncleanness, with proper remedies and arguments proposed: some further cautions are added, and other duties recommended. Filthy lusts must be suppressed, in order to the supporting of holy love. Walk in love, and shun fornication and all uncleanness. Fornication is folly committed between unmarried persons. All uncleanness includes all other sorts of filthy lusts, which were too common among the Gentiles.
Commenting on Ephesians 5:3-20
For it is a shame even to speak of those things,.... This is a reason, why persons should walk as children of light; why they should prove what is acceptable to God; why they should have no fellowship with the unfruitful works of darkness; why the apostle exhorts to reprove them, and yet does not express what they are; and why they should be reproved...
Verse 10. Proving what is acceptable unto the Lord. That is, "Walk as children of light, , thus showing what is acceptable to the Lord." Rosenmuller supposes that the participle is used here instead of the imperative. The meaning is, that by so living you will make a fair trial of what is acceptable to the Lord.