What does Psalm 118:21 mean?

At the beginning of the psalm (Psalm 118:1–5), the writer praised the Lord for providing rescue from danger. Much of what follows seems to speak for the nation of Israel (Psalm 118:10–16). In the immediate context, this prior danger is what the psalmist is describing. The Lord gave a favorable answer, so the psalmist—and Israel—were preserved (Psalm 118:17–18). The Lord had become salvation: the means by which Israel was spared from destruction.

Events in Israel's history gave them ample reason to praise God for their rescue. They had been rescued from Egypt (Exodus 12:41) and brought back alive from exile (Ezra 2:1; 3:1–2, 8). Then the Lord had protected them while the city and temple were rebuilt (Nehemiah 4:14; 6:16).

This passage parallels the New Testament explanation of the gospel. The "righteous" here are those who honor God (Proverbs 1:7) and enter through a gate (Psalm 118:19–20). That gate is Jesus Christ (Matthew 7:13–14; John 10:9). In Him, they find salvation (Acts 4:12). The book of Acts makes this point and connects to this very psalm (Acts 4:11; Psalm 118:22).

In truth, God "answers" all prayers; the answer is sometimes, "no." Prayers not aligned with His will cannot be approved (1 John 5:14). Yet Scripture encourages believers to bring all their thoughts and fears to the Lord in prayer. Those who sincerely seek Him will get an answer (Jermiah 33:2–3; Matthew 7:7, 11). Failure to ask in sincerity, or at all, shows a lack of faith (James 4:2–3).