Summary
David asks the LORD to take up his case as an advocate takes a brief, and to take up shield and spear as a soldier does. The psalm moves through three cycles, each running the same course: the wrong described, the judgment asked, and a vow of praise when it comes. What is asked for is exposure and reversal — the pit they dug, the net they hid, closing over the hands that set them.
The wound is that this hatred answers kindness: he had fasted and mourned for these men as for a brother. He does not repay it; he hands it over. Christ takes verse 19 on His own lips in the upper room — they hated Me without a cause — so the psalm is sung after Him, and its vow of thanks in the great congregation is the note it means to end on.
Outline
Take up my case and my defence; let their own net take them; then my soul shall be joyful in the LORD.
False witnesses rise; he recalls the fasting and mourning he spent on them, and asks how long God will look on.
The wink of the eye, the wide-open mouth; a plea that God judge according to His righteousness, and that those who love the cause rejoice.
Stanza divisions provisional — to be conformed to the Book of Psalms for Worship. References NASB.