Verses 4-6. - The Almighty is introduced as making a revelation to the psalmist. He will cause the Gentiles to flock into his Church, even those who have been hitherto the most bitter enemies of Israel (ver. 4), and will place these strangers on a par with such as have belonged to his Church from their birth (vers. 4, 5, 6), admitting them to every blessing and every privilege. The Church, thus augmented, shall be taken under his own protection, and "established," or placed on a sure footing, forever. Compare our Lord's promise to St. Peter," On this rock will I build my Church, and the gates of hell shall not prevail against it" (Matthew 16:18). Verse 4. - I will make mention of Rahab; i.e. of Egypt. The context requires this meaning, which is found also in Psalm 89:10 and in Isaiah 51:9. Literally "Rahab" means "pride, arrogance." And Babylon. The fitting counterpart of Egypt, equally antagonistic to Israel, and equally lifted up with pride and presumption. To them that know me; rather, among them that know me; i.e. as belonging to them, included in their number (comp. Isaiah 19:21, "And the Lord shall be known to the Egyptians, and the Egyptians shall know the Lord in that day;" and see also Psalm 72:11, 17; Psalm 82:8; Isaiah 66:23). Behold Philistia, and Tyre, with Ethiopia. Other hostile nations (comp. Psalm 83:7; 2 Chronicles 12:3; 2 Chronicles 14:9-13). This man was horn there. There is no "man" in the original, and it is better to understand "nation;" this, that, and the other nation - all those mentioned, and others - are grafted into Zion, and have a second birth there.