Prayer (40:12). The brief element of prayer forms an appropriate transition between the thanksgiving for former acts of deliverance, and the lament (vv 13–17) which will culminate in an explicit prayer for a future act of deliverance (v 18). The whole thrust of the prayer is to be found in the imperative: “come.” The king prays for the divine presence in the approaching crisis, for it had only been that presence which converted former crisis into victory. The divine presence would bring with it those covenant characteristics of God (“mercies, lovingkindness, truth”) that would provide the necessary protection (v 12b) in crisis and would culminate in victory.

PETER C. CRAIGIE AND MARVIN TATE, PSALMS 1-50, VOLUME 19: SECOND EDITION (WORD BIBLICAL COMMENTARY), 316.