The words are remarkable because they imply that in the heart of Judaism there lurked a yearning for another and different kind of priesthood from that of Aaron’s order. It may be compared to the strange intrusion now and again of other gods than the deities of Olympus into the religion of the Greeks, either by the introduction of a new deity or by way of return to a condition of things that existed before the young gods of the court of Zeus began to hold sway. But, to add to the mysterious character of the Psalm, it gives utterance to a desire for another King also, Who should be greater than a mere son of David: “The Lord said unto my Lord, Sit Thou at My right hand, until I make Thine enemies Thy footstool.” Yet the Psalmist is David himself, and Christ silenced the Pharisees by asking them to explain the paradox: “If David then call Him Lord, how is He his Son?”[118] Delitzsch observes “that in no other psalm does David distinguish between himself and Messiah;” that is, in all his other predictions Messiah is David himself idealised, but in this Psalm He is David’s Lord as well as his Son. The Psalmist desires a better priesthood and a better kingship. These aspirations are alien to the nature of Judaism. The Mosaic dispensation pointed indeed to a coming priest, and the Jews might expect Messiah to be a King. But the Priest would be the antitype of Aaron, and the King would be only the Son of David. The Psalm speaks of a Priest after the order, not of Aaron, but of Melchizedek, and of a King Who would be David’s Lord. To increase the difficulty, the Priest and the King would be one and the same Person. Yet the Psalmist’s mysterious conception comes to the surface now and again. In the Book of Zechariah the Lord commands the prophet to set crowns upon the head of Joshua the high-priest, and proclamation is made “that he shall be a priest upon his throne.”[119] The Maccabæan princes are invested with priestly garments. Philo[120] has actually anticipated the Apostle in his reference to the union of the priesthood and kingship in the person of Melchizedek. We need not hesitate to say that the Apostle borrows his allegory from Philo, and finds his conception of the Priest-King in the religious insight of the profounder men, or at least in their earnest groping for better things. All this notwithstanding, his use of the allegory is original and most felicitous. He adds an idea, fraught with consequences to his argument. For the central thought of the passage is the endless duration of the priesthood of Melchizedek. The Priest-King is Priest for ever.