Who the Instructor Is, and Respecting His Instruction
It is He also who teaches Moses to act as instructor. For the Lord says, “If any one sin before Me, him will I blot out of My book; but now, go and lead this people into the place which I told you.” Here He is the teacher of the art of instruction. For it was really the Lord that was the instructor of the ancient people by Moses; but He is the instructor of the new people by Himself, face to face. “For behold,” He says to Moses, “My angel shall go before you,” representing the evangelical and commanding power of the Word, but guarding the Lord's prerogative. “In the day on which I will visit them,” He says, “I will bring their sins on them; that is, on the day on which I will sit as judge I will render the recompense of their sins.” For the same who is Instructor is judge, and judges those who disobey Him; and the loving Word will not pass over their transgression in silence. He reproves, that they may repent. For “the Lord wills the repentance of the sinner rather than his death.” And let us as babes, hearing of the sins of others, keep from similar transgressions, through dread of the threatening, that we may not have to undergo like sufferings. What, then, was the sin which they committed? “For in their wrath they slew men, and in their impetuosity they hamstrung bulls. Cursed be their anger.” Who, then, would train us more lovingly than He? Formerly the older people had an old covenant, and the law disciplined the people with fear, and the Word was an angel; but to the fresh and new people has also been given a new covenant, and the Word has appeared, and fear is turned to love, and that mystic angel is born— Jesus. For this same Instructor said then, “You shall fear the Lord God;” but to us He has addressed the exhortation, “You shall love the Lord your God.” Wherefore also this is enjoined on us: “Cease from your own works, from your old sins;” “Learn to do well;” “Depart from evil, and do good;” “You have loved righteousness, and hated iniquity.” This is my new covenant written in the old letter. The newness of the word must not, then, be made ground of reproach. But the Lord has also said in Jeremiah: “Say not that I am a youth: before I formed you in the belly I knew you, and before I brought you out of the womb I sanctified you.” Such allusions prophecy can make to us, destined in the eye of God to faith before the foundation of the world; but now babes, through the recent fulfilment of the will of God, according to which we are born now to calling and salvation. Wherefore also He adds, “I have set you for a prophet to the nations,” saying that he must prophesy, so that the appellation of “youth” should not become a reproach to those who are called babes.
Now the law is ancient grace given through Moses by the Word. Wherefore also the Scripture says, “The law was given through Moses,” not by Moses, but by the Word, and through Moses His servant. Wherefore it was only temporary; but eternal grace and truth were by Jesus Christ. Mark the expressions of Scripture: of the law only is it said “was given;” but truth being the grace of the Father, is the eternal work of the Word; and it is not said to be given, but to be by Jesus, without whom nothing was. Presently, therefore, Moses prophetically, giving place to the perfect Instructor the Word, predicts both the name and the office of Instructor, and committing to the people the commands of obedience, sets before them the Instructor. “A prophet,” says he, “like Me shall God raise up to you of your brethren,” pointing out Jesus the Son of God, by an allusion to Jesus the son of Nun; for the name of Jesus predicted in the law was a shadow of Christ. He adds, therefore, consulting the advantage of the people, “Him shall you hear;” and, “The man who will not hear that Prophet,” him He threatens. Such a name, then, he predicts as that of the Instructor, who is the author of salvation. Wherefore prophecy invests Him with a rod, a rod of discipline, of rule, of authority; that those whom the persuasive word heals not, the threatening may heal; and whom the threatening heals not, the rod may heal; and whom the rod heals not, the fire may devour. “There shall come forth,” it is said, “a rod out of the root of Jesse.”
See the care, and wisdom, and power of the Instructor: “He shall not judge according to opinion, nor according to report; but He shall dispense judgment to the humble, and reprove the sinners of the earth.” And by David: “The Lord instructing, has instructed me, and not given me over to death.” For to be chastised of the Lord, and instructed, is deliverance from death. And by the same prophet He says: “You shall rule them with a rod of iron.” Thus also the apostle, in the Epistle to the Corinthians, being moved, says, “What will you? Shall I come unto you with a rod, or in love, in the spirit of meekness?” Also, “The Lord shall send the rod of strength out of Sion,” He says by another prophet. And this same rod of instruction, “Your rod and staff have comforted me,” said some one else. Such is the power of the Instructor— sacred, soothing, saving.
Source: The Instructor (New Advent)