John Gill Commentary Psalms 59:10

"My God with his lovingkindness will meet me: God will let me see [my desire] upon mine enemies." — Psalms 59:10 (ASV)

The God of my mercy shall prevent me
Or "of my grace", or "goodness", as the Targum; see (1 Peter 5:10). God is gracious in himself, and he has treasured up a fulness of grace in Christ: he is the donor of all the blessings of grace in the covenant; and the author of all internal grace in the hearts of his people; and who supplies them with more grace as they want it; and he is the Father of all temporal and spiritual mercies. The "Cetib", or writing, is (wdox) , "his mercy"; the "Keri", or reading, is (ydox) , "my mercy"; grace or mercy is the Lord's; it is his own, which he disposes of as he pleases; being given and applied, it is the believer's; all the grace and mercy in the heart of God, in his Son, and in his covenant, is the saints', which he keeps for them with Christ for evermore; "the God of my mercy", or "grace", is the same with "my merciful", or "my gracious God"; who goes before his people, as he does the Messiah, with the blessings of his goodness, (Psalms 21:3). It may be rendered, "has come before me"; and denote the antiquity of his love, being before his people's to him, and the early provisions of his grace and mercy for them: or "does prevent me": expressing the freeness of it; he not waiting for any duties, services, or conditions to be performed, but bestows his grace and mercy, notwithstanding much unworthiness: or "shall come before me"; designing the seasonable and timely application of mercy come before his fears, as it sometimes does the prayers of his people, (Isaiah 65:24).

God shall let me see [my desire] upon mine enemies ;
expressed in the following verses, (Psalms 59:11–15); or "vengeance upon them"; as the Targum paraphrases it; see (Psalms 58:10).