Charles Ellicott Commentary Ephesians 5:10

"proving what is well-pleasing unto the Lord;" — Ephesians 5:10 (ASV)

Proving what is acceptable unto the Lord.—So in Romans 12:2, the proving what is the good and acceptable and perfect will of God, is the fruit of transformation in the renewing of the mind. “To prove” is to try in each case, by the full light of God, what is according to His will; it is a work partly of thought, partly of practical experience; and it always implies a searching examination of heart and action by the touchstone of God’s word.