John Gill Commentary Ephesians 5:13

"But all things when they are reproved are made manifest by the light: for everything that is made manifest is light." — Ephesians 5:13 (ASV)

But all things that are reproved
As all sins should be, by the ministers of the Gospel, and by other saints, and will be by God; either by his Spirit convincing of them, or by his judgments, and the letting out of his wrath and fury, either here or hereafter, for the punishment of them:

are made manifest by the light :
either by the saints, who are made light in the Lord, and detect and reprove the sins of others; or by the word of the Lord, which discovers the heinousness of sins; or by Christ the light of the world, who as Judge will bring to light the hidden things of darkness; or by the omniscience of God, to whom darkness and light are both alike

for whatsoever doth make manifest, is light ;
this is true in things natural and spiritual, whether of the sun in the firmament, or of Christ the sun of righteousness; or of the divine word, or of good men.