According to all that thou desiredst of the Lord thy God at Horeb,.... This was promised them, in answer to their request at Horeb or Mount Sinai, when the law was delivered to them in the terrible manner it was: in the day of the assembly; in which the tribes were gathered together to receive the law, when they were assembled at the foot of the mount for that purpose:

saying, let me not hear again the voice of the Lord my God; which was such a voice of words, attended with so much terror, that they that heard entreated the word might not be spoken to them any more, as the apostle says in Hebrews 12:19,

neither let me see this great fire any more, that I die not; out of which the Lord spoke; the congregation of Israel is here represented speaking as if a single person.

With this assurance the Lord had fully granted the request of the people, "according to all that thou desiredst of the Lord thy God;" and Israel, therefore, was all the more bound to hearken to the prophets, whom God would raise up from the midst of itself, and not to resort to heathen soothsayers. (On the fact itself, comp. Deuteronomy 5:20. with Exodus 20:15-17.) "In the day of the assembly," as in Deuteronomy 9:10; Deuteronomy 10:4. - The instructions as to their behaviour towards the prophets are given by Moses (Deuteronomy 18:19, Deuteronomy 18:20) in the name of the Lord, for the purpose of enforcing obedience with all the greater emphasis. Whoever did not hearken to the words of the prophet who spoke in the name of the Lord, of him the Lord would require it, i.e., visit the disobedience with punishment (cf. Psalm 10:4, Psalm 10:13). On the other hand, the prophet who spoke in the name of the Lord what the Lord had not commanded him, i.e., proclaimed the thoughts of his own heart as divine revelations (cf. Numbers 16:28), should die, like the prophet who spoke in the name of other gods. With וּמת, the predicate is introduced in the form of an apodosis.

According to all that thou desiredst of the LORD thy God in Horeb in the day of the assembly, saying, Let me not hear again the voice of the LORD my God, neither let me see this great fire any more, that I die not.

18:15-22 It is here promised concerning Christ, that there should come a Prophet, great above all the prophets; by whom God would make known himself and his will to the children of men, more fully and clearly than he had ever done before. He is the Light of the world, Joh 8:12. He is the World by whom God speaks to us, Joh 1:1; Heb 1:2. In his birth he should be one of their nation. In his resurrection he should be raised up at Jerusalem, and from thence his doctrine should go forth to all the world. Thus God, having raised up his Son Christ Jesus, sent him to bless us. He should be like unto Moses, only above him. This prophet is come, even JESUS; and is He that should come, and we are to look for no other. The view of God which he gives, will not terrify or overwhelm, but encourages us. He speaks with fatherly affection and Divine authority united. Whoever refuses to listen to Jesus Christ, shall find it is at his peril; the same that is the Prophet is to be his Judge, Joh 12:48. Woe then to those who refuse to hearken to His voice, to accept His salvation, or yield obedience to His sway! But happy they who trust in Him, and obey Him. He will lead them in the paths of safety and peace, until He brings them to the land of perfect light, purity, and happiness. Here is a caution against false prophets. It highly concerns us to have a right touchstone wherewith to try the word we hear, that we may know what that word is which the Lord has not spoken. Whatever is against the plain sense of the written word, or which gives countenance or encouragement to sin, we may be sure is not that which the Lord has spoken.