This phrase implies that God will come to him in order to save him. The abstract noun "faithfulness" can be translated with an adjective. Alternate translation: "My God, who is faithful to his covenant, will come to save me" or "My God will come to save me because he is faithful to his covenant" (See: [[rc://en/ta/man/translate/figs-explicit]] and [[rc://en/ta/man/translate/figs-abstractnouns]])
The abstract noun "desire" can be expressed with the verb "want." Alternate translation: "what I want to happen to my enemies" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])