Albert Barnes Commentary Psalms 72:11

"Yea, all kings shall fall down before him; All nations shall serve him." — Psalms 72:11 (ASV)

Yea, all kings shall fall down... - That is, his reign will be universal. The kings and people mentioned in the previous verses are only specimens of what will occur. All kings - all nations - will do what these are represented as doing. They will submit to the Messiah; they will own him as their Lord. See the notes at Psalms 2:8. Compare Isaiah 49:23.