Like David, you need God’s deliverance from two different enemies.
Those who attack you (1–10). There are places in this world where it is a dangerous thing to be a Christian, and their number may increase. After all, Satan is a murderer (John 8:44) and would destroy all of God’s people if he could. But the Lord fights for us. He has effective weapons (vv. 2–3) and knows the enemy’s plots (v. 4). If you belong to the Lord, He is responsible to care for you.
Those who accuse you (11–28). Satan is an accuser as well as a murderer (Rev. 12:10), so David had to move from the battlefield to the courtroom where his enemies were lying about him. His prayer changed from “Fight for me!” to “Vindicate me!” (vv. 23–24). But his concern was that God’s name, not his own, be magnified (v. 27). When the enemy slanders your name, he attacks the name of the Lord as well.
Note the results: “And my soul shall be joyful” (v. 9); “And my tongue shall speak of Your righteousness” (v. 28). Joy on the inside and witness on the outside!