What does Psalm 22:21 mean?

This verse finds David exulting in the Lord for delivering him. He prays to be delivered from the mouth of the lion, but then says the Lord has rescued him from the horns of wild oxen. This completes a pattern often seen in the Old Testament: chiasm, or a "mirror image." David compared his enemies to bulls (Psalm 22:12), lions (Psalm 22:13) and dogs (Psalm 22:16). In this verse and the previous verse he reverses that order with prayers referring to dogs (Psalm 22:20), lions, and bulls.

All of this prophetically describes the suffering of Jesus during His crucifixion. These words express not only David's gratitude to his personal God—"You"—but also Jesus' delight at being raised from the dead. The Devil, a roaring lion (1 Peter 5:8), was unable to defeat Jesus. In fulfillment of Genesis 3:15 the old serpent, the Devil, would bruise Jesus the Messiah's heel, but Jesus the Messiah, "the seed" of the woman, would bruise the serpent's head.

David's deliverance from his foes came from the Lord who answered his prayer. The deliverance was like that of being rescued from the horns of wild oxen. Similarly, Jesus' crucifixion ended in a triumphant resurrection. Hebrews 12:2 refers to Jesus as "the founder and perfecter of our faith, who for the joy that was set before him endured the cross, despising the shame, and is seated at the right hand of the throne of God." The agony of Calvary ended; the glory of resurrection and ascension followed.