" 15. He has opened a pit, etc. This is the wonderful wisdom of God, that He does not punish the ungodly except with their own stratagems, He mocks them with their own mockeries, He pierces them with their own javelins, as David did with Goliath and Christ did with the devil. Thus the Jews had prepared every evil for Christ, and behold, it came upon themselves. And always God observes the rule: “No law is fairer than that the schemers of destruction perish by their own device.”8 And blessed Augustine says, “You have commanded,9 O Lord, and so it is done, that every disordered spirit be its self-punishment.”10 And in this passage (v. 16) we read: His mischief shall be turned on his own head. This is what happened to Saul, Absalom, and many others who harmed themselves when they wanted to harm others, and the fact that Saul fell on his own sword, and his armor bearer after him, is an illustration of this. "

― Martin Luther , Lectures on the Psalms I: Chapters 1-75 (Luther's Works, #10)