Psalms 72:8

8He shall have dominion from sea to sea. As the Lord, when he promised his people the land of Canaan for an inheritance, assigned to it these four boundaries, (Genesis 15:18,) David intimates, that so long as the kingdom shall continue to exist, the possession of the promised land will be entire, to teach the faithful that the blessing of God cannot be fully realised, except whilst this kingdom shall flourish. He therefore declares that he will exercise dominion from the Red Sea, or from that arm of the Egyptian sea to the sea of Syria, which is called the Sea of the Philistines, (134) and also from the river Euphrates to the great wilderness. If it is objected that such narrow bounds do not correspond with the kingdom of Christ, which was to be extended from the rising of the sun to the going down thereof, we reply, that David obviously accommodates his language to his own time, the amplitude of the kingdom of Christ not having been, as yet, fully unfolded. He has therefore begun his description in phraseology well known, and in familiar use under the law and the prophets; and even Christ himself commenced his reign within the limits here marked out before he penetrated to the uttermost boundaries of the earth; as it is said in Psalms 110:2,

“The Lord shall send the rod of thy strength out of Zion.”

But, soon after, the Psalmist proceeds to speak of the enlarged extent of the empire of this king, declaring that the kings beyond the sea shall also be tributaries to him; and also that the inhabitants of the desert shall receive his yoke. The word ציים, tsiim, (135) which we have translated inhabitants of the desert, is, I have no doubt, to be understood of those who, dwelling towards the south, were at a great distance from the land of Canaan. The Prophet immediately adds, that the enemies of the king shall lick the dust in token of their reverence. This, as is well known, was in ancient times a customary ceremony among the nations of the East; and Alexander the Great, after he had conquered the East, wished to compel his subjects to practice it, from which arose great dissatisfaction and contentions, the Macedonians disdainfully refusing to yield such a slavish and degrading mark of subjection. (136) The meaning then is, that the king chosen by God in Judea will obtain so complete a victory over all his enemies, far and wide, that they shall come humbly to pay him homage.