Psalm 7

Falsely accused, David asks God to judge, and he includes himself: "if injustice is on my hands... then may my enemy pursue me." He's willing to be examined, not only vindicated. Evil is pictured as a pregnancy that births its own ruin; the pit-digger falls in.

"His trouble recoils on himself, and his violence falls on his own head." (Psalm 7:16)