Augustine of Hippo

"The Lord is known executing judgments" [Psalm 9:16]. These are God's judgments. Not from that tranquillity of His blessedness, nor from the secret places of wisdom, wherein blessed souls are received, is the sword, or fire, or wild beast, or any such thing brought forth, whereby sinners may be tormented: but how are they tormented, and how does the Lord do judgment? "In the works," he says, "of his own hands hath the sinner been caught."

Here is interposed, "The song of the diapsalma" [Psalm 9:16]: as it were the hidden joy, as far as we can imagine, of the separation which is now made, not in place, but in the affections of the heart, between sinners and the righteous, as of the corn from the chaff, as yet on the floor.