What does Psalm 122:7 mean?

This follows a request for prayer (Psalm 122:6) on behalf of Jerusalem (Psalm 122:3–6), where pilgrims would travel for yearly festivals (Psalm 122:1–2; Deuteronomy 16:16). Here, the psalmist specifically prays for physical protection over the city. Walls and towers were primary defensive measures in the ancient world. To see these intact would encourage Israelites about the Lord's provision (Psalm 48:13–14).

Unfortunately, because of Israel's constant rejection of the Lord, the city has experienced mostly strife and warfare. Idol worship and sin led the nation to be conquered and scattered (2 Chronicles 36:17–20). Centuries after returning from exile, the leadership of the city rejected Jesus Christ, their promised Messiah. This led to a loss of peace (Matthew 23:37–38; 24:1–2) including the complete destruction of the temple in AD 70.

Since then, Jerusalem has been a place of nearly constant conflict and war. This will end only when Jesus returns to defeat all evil (Revelation 19:11–16), rule the world for a thousand years (Revelation 20:4) and then take His throne for eternity in the New Jerusalem (Revelation 21:1–4).