Eran.— The promise goes beyond the bounds of human nature, for both the life and the honour are indestructible and eternal. But men endure but for a season; their nature is short lived and their kingdom even during its lifetime undergoes many and various vicissitudes, so that truly the greatness of the prophecy befits none but the Saviour Christ.
Orth.— Go on then to what follows and your opinion upon this point will be in every way confirmed, for again says the God of the universe, “Once have I sworn by my holiness, if I lie unto David, his seed shall endure for ever and his throne as the sun before me. It shall be established for ever as the moon.”
Then, pointing out the truth of the promise He adds, “And the witness is faithful in heaven.”
Eran.— We must believe without doubt in the promises given by the faithful witness, for, if we are wont to believe men who have promised to speak the truth even if they do not confirm their words with an oath, who can be so mad as to disbelieve the Creator of the Universe, when He adds an oath to his words? For He who forbids others to swear confirmed the immutability of his counsel by an oath, “that by two immutable things in which it was impossible for God to lie we might have a strong consolation who have fled for refuge to lay hold upon the hope set before us.”
Orth.— If then the promise is irrefragable, and among the Jews there is now neither family nor kingdom of the prophet David to be seen, let us believe that our Lord Jesus Christ is plainly called seed of David in His humanity, for of Him the life and the kingdom are both alike eternal.
Eran.— We have no doubt; and this I own to be the truth.
Orth.— These proofs then are sufficient to show clearly the manhood which our Lord and Saviour took of David's seed. But to remove all possibility of doubt by the witness of the majority, let us hear how God makes mention of the promises given to David through the voice of the prophet Isaiah. “I will make,” he says, “an everlasting covenant with you,” and, signifying the law-giver, he adds, “even the sure mercies of David.”
Since He made this promise to David, and spoke through Esaias, He will assuredly bring the promise to pass. And what follows after the prophecy is in harmony with what I say, for he says “Behold I have given him for a witness to the people, a leader and commander to the people. Behold nations that know you not shall call upon you, and peoples that understand you not shall run unto you.” Now this fits in with none that are sprung from David, for who of David's descendants, as Esaias says, was made a ruler of nations? And what nations in their prayers ever called on David's descendants as God?
Eran.— About what is perfectly clear it is unbecoming to dispute, and this plainly refers to the Lord Christ.
Orth.— Then let us pass on to another prophetic testimony and let us hear the same prophet saying “There shall come forth a rod out of the stem of Jesse and a branch shall grow out of his roots.”
Eran.— I think this prophecy was delivered about Zerubbabel.
Orth.— If you hear what follows, you will not remain in your opinion. The Jews have never so understood this prediction, for the prophet goes on, “and the Spirit of the Lord shall rest upon him, the spirit of wisdom and understanding, the spirit of counsel and might, the spirit of knowledge and the fear of the Lord.” This would never be attributed by any one to a mere man, for even to the very holy the gifts of the Spirit are given by division, as the divine apostle witnesses when he says, “To one is given by the Spirit the word of wisdom, to another the word of knowledge by the same Spirit,” and so on. The prophet describes Him who sprang from the root of Jesse as possessing all the powers of the spirit.
Eran.— To gainsay this were sheer folly.
Orth.— Now hear what follows. You will see some things that transcend human nature, he goes on. “He shall not judge after the sight of His eyes, neither reprove after the hearing of His ears, but with righteousness shall He judge the poor, and reprove with equity the mighty of the earth, and He shall smite the earth with the word of His mouth, and with the breath of His lips shall he slay the wicked.” Now of these predictions some are human and some divine. Justice, truth, equity, and rectitude in giving judgment exhibit virtue in human nature.
Eran.— We have so far clearly learned that the prophet predicts the coming of our Saviour Christ.
Orth.— The sequel will show you yet more plainly the truth of the interpretation. For he goes on, “The wolf shall dwell with the lamb,” and so on, whereby he teaches at once the distinction of modes of life and the harmony of faith; and experience furnishes a proof of the prediction, for they that abound in wealth, they that live in poverty, servants and masters, rulers and ruled, soldiers and citizens and they that wield the sceptre of the world are received in one font, are all taught one doctrine, are all admitted to one mystic table, and each of the believers enjoys an equal share.
Eran.— It is thus shown that God is spoken of.
Orth.— Not only God but man. So at the very beginning of this prediction he says that a rod shall grow out of the root of Jesse. Then at the conclusion of the prediction he takes up once more the strain with which he began, for he says “There shall be a root of Jesse which shall stand for an ensign of the people, to it shall the Gentiles seek and his rest shall be glorious.” Now Jesse was the father of David, and the promise with an oath was made to David. The prophet would not have spoken of the Lord Christ as a rod growing out of Jesse if he had only known Him as God. The prediction also foretold the change of the world, for “the earth” he says “shall be full of the knowledge of the Lord as the waters cover the sea.”
Eran.— I have heard the prophetic utterances. But I was anxious to know clearly if the divine company of the apostles also says that the Lord Christ sprang from the seed of David according to the flesh.
Orth.— You have asked for information which so far from being hard is exceedingly easy to give you. Only listen to the first of the apostles exclaiming “David being a prophet and knowing that God had sworn an oath to him that of the fruit of his loins, according to the flesh, He would raise up Christ to sit upon His throne; he seeing this before spoke of the resurrection of Christ, that His soul was not left in hell neither His flesh did see corruption.”
Hence you may perceive that of the seed of David according to the flesh sprang the Lord Christ, and had not flesh only but also a soul.
Eran.— What other apostle preached this?
Orth.— The great Peter alone was sufficient to testify to the truth, for the Lord after receiving the confession of the truth given by Peter alone confirmed it by a memorable approval. But since you are anxious to hear others proclaiming this same thing, hear Paul and Barnabas preaching in Antioch in Pisidia; for they, when they had made mention of David, continued “Of this man's seed has God according to his promise raised unto Israel a Saviour, Jesus,” and so on. And in a letter to Timothy the divine Paul says “Remember that Jesus Christ of the seed of David was raised from the dead according to my gospel.” And, when writing to the Romans, at the very outset he calls attention to the Davidic kin, for he says “Paul a servant of Jesus Christ, called to be an apostle, separated unto the gospel of God which He had promised before by his prophets in the holy scriptures concerning His Son which was made of the seed of David according to the flesh,” and so on.
Eran.— Your proofs are numerous and convincing; but tell me why you have omitted what follows?
Source: Dialogues ("Eranistes" or "Polymorphus") (New Advent)