Albert Barnes Commentary Psalms 72:12

"For he will deliver the needy when he crieth, And the poor, that hath no helper." — Psalms 72:12 (ASV)

For he shall deliver the needy when he crieth - The sufferer; the down-trodden; the oppressed. See the notes at (Psalms 72:4). Compare the notes at (Isaiah 61:1).

The poor also... - All who have no protector; all who are exposed to injustice and wrong from others. This is everywhere declared to be the characteristic of the reign of the Messiah. See the notes at (Isaiah 11:4).