This is a prayer before the battle, and Psalm 21 is the praise after the victory. In verses 1–5, the people pray for their king (we/you); David the king encourages the people in verses 6–8 (I/we/they); and both the king and the people speak in verse 9, where “the king” is Jehovah God, The King. The psalm begins and ends with a plea for God to hear them as they pray and to give victory to the army of Israel (vv. 1, 9). The anointed king was the very life and breath of the nation (Lam. 4:20) and the lamp of Israel (2 Sam. 21:17), and the enemy soldiers would make him their special target (1 Kings 22:31). Those who have problems with the military aspects of some of David’s psalms should remember that David went to war only when the enemy attacked Israel. He did not invade other nations just to gain territory, and he was fighting the Lord’s battles (1 Sam. 17:47; 25:28; 2 Chron. 20:15). The covenant God made with David (2 Sam. 7:11) assured him of victory over his enemies. In this regard, David is a picture of our Lord Jesus Christ, the Commander of the Lord’s armies (Josh. 5:14–15), who one day will ride in victory against the armies of this world (Ps. 45:3–7; Rev. 3:14; 17:14; 19:11–21). Just as physicians fight a battle against disease and death, so our Lord wages a war against sin and evil. “Lord Sabaoth His name / From age to age the same / And He must win the battle” (Martin Luther). This psalm describes three essentials for victory as God’s people fight against the forces of evil.
A Praying People (vv. 1–5)
Before the army went out to battle, the Jewish law of warfare required the officers and soldiers first to dedicate themselves to the Lord (Deut. 20:1–4), and this psalm speaks of such a dedication service. “Battles are won the day before,” said Marshall Foch, commander of the Allied forces in World War I. The word “may” is used six times in verses 1–5 as the people prayed for their king (see NASB, NIV). Not only were the lives of the king and his army involved, but so also was the glory of the Lord (vv. 5, 7). It was a “day of trouble” (see 50:15; 59:16; 77:2; 86:7; 102:2), but Jehovah is a “very present help in trouble” (Ps. 46:1). In verse 1, the people prayed that God would answer the king’s prayers and lift him up above the enemy (“defend”). “The God of Jacob” is a familiar title for the Lord (24:6; 46:7, 11; 75:9; 76:6; 81:1, 4; 84:8; 94:7; 114:7; 132:2, 5; 146:5; and see Isa. 49:26 and 60:16). It suggests that God works on behalf of those who are weak and in special need (see Gen. 35:1–3).
David had brought the ark of the covenant to Mt. Zion (2 Sam. 6), which meant that God was enthroned among His people and would help them (Pss. 80:1 and 99:1, NIV). His holy name was upon the sanctuary (Deut. 14:23; 16:2, 11), and therefore His glory was at stake. Many times David had brought sacrifices to the altar and dedicated himself to the Lord (burnt offerings) and given thanks to Him, and he would have offered sacrifices before coming to lead the army. (See 1 Sam. 7:9ff and 13:9ff.) The Lord did not forget these offerings which were given as memorials to His great name (Lev. 2:1–2, 9, 16; 5:12; and see Acts 10:4). But David had done more than worship God; he had also sought the Lord’s will concerning strategy for the battle (see 1 Sam. 23). The people prayed that God would bless those plans, for petitions and plans must go together. The central verse in the psalm is verse 5, a confident affirmation of victory before the battle even started. Raising the banners and waving them was a sign of victory, and “Jehovah our banner” was one of God’s special names (see Ex. 17:15–16). The theme of salvation (victory) is repeated in verses 6 and 9.
A Confident Leader (vv. 6–8)
“Everything rises and falls with leadership,” Dr. Lee Roberson often says, and he is right. Now the king speaks and assures his people that he is confident of success because the Lord has chosen him (“anointed”) and heard his prayers. The people had prayed “May the Lord hear” (v. 1) and David’s reply was, “He will hear” (v. 6). The Lord would not only send help from Zion (v. 2) but also from the very throne of heaven! (v. 6). Just as God’s hand had reached down and saved David in the past (18:9–18), so His hand would deliver him from the enemy. In the covenant God made with David, He had promised him success in battle (2 Sam. 7:11), and David claimed this promise by faith.
Was the enemy coming with horses and chariots? There was no need to fear, for Israel’s faith was in the Lord. Israel’s kings were commanded not to acquire great numbers of horses and chariots (Deut. 17:16), a law that Solomon disobeyed (1 Kings 10:26–27). Note that the law of warfare even mentions horses and chariots (Deut. 20:1–4, and see 32:20 and 2 Sam. 10:18). God had defeated Egypt’s best troops (Ex. 14:6ff; 15:4), and He could defeat the enemy attacking David (Ps. 33:16–17; Prov. 21:31; 2 Kings 19:20–23). “If God be for us, who can be against us?” (Rom. 8:31). God’s people don’t boast in their human resources but in the God who alone can save them in every situation. Only this kind of faith will honor the strong name of the Lord. The enemy will go down in defeat, but Israel will stand upright as victors.
A Sovereign Lord (v. 9)
Translators don’t agree as to whether “king” in this verse refers to David or to the Lord, the King of Israel (5:2; 10:16; 48:1–2; 84:3; 95:3; 145:1). The Prayer Book Version of the Psalms reads, “Save, Lord, and hear us, O King of heaven, when we call upon thee”; and the English Revised Version reads, “Save Lord: Let the King answer us when we call.” The American Standard Version also reads “King,” and so does the New American Standard Bible. But whether “king” refers to David or to the Lord, verse 9 affirms that the Lord is sovereign because He hears prayer and is able to answer. I prefer “King,” and I can see David, the people, and the troops acknowledging the sovereignty of the great king of Israel. Unless the Lord is King, there can be no victory. “For the Lord is the great God, the great King above all gods” (95:3, NIV). “The Lord Almighty—he is the King of Glory” (24:10, NIV). David plans his strategy (v. 4), but the Lord alone can determine the outcome.