Moses is speaking here telling them what God said to him in his law it’s prophetic foretelling another to come later
“I will raise them up a Prophet from among their brethren, like unto thee, and will put my words in his mouth; and he shall speak unto them all that I shall command him. And it shall come to pass, that whosoever will not hearken unto my words which he shall speak in my name, I will require it of him.”
Deuteronomy 18:18-19 KJV
Jesus claimed to be the one God sent and said this of his word
“He that rejecteth me, and receiveth not my words, hath one that judgeth him: the word that I have spoken, the same shall judge him in the last day.
For I have not spoken of myself; but the Father which sent me, he gave me a commandment, what I should say, and what I should speak. And I know that his commandment is life everlasting: whatsoever I speak therefore, even as the Father said unto me, so I speak.”
John 12:48-50 KJV
Peter later filled with the Holy Ghost says of Jesus
“For Moses truly said unto the fathers, A prophet shall the Lord your God raise up unto you of your brethren, like unto me; him shall ye hear in all things whatsoever he shall say unto you. And it shall come to pass, that every soul, which will not hear that prophet, shall be destroyed from among the people.
Yea, and all the prophets from Samuel and those that follow after, as many as have spoken, have likewise foretold of these days. Ye are the children of the prophets, and of the covenant which God made with our fathers, saying unto Abraham, And in thy seed shall all the kindreds of the earth be blessed. ( not the covenant made through Moses at Sinai for only israel but with Abraham before that for all people ) Unto you first God, having raised up his Son Jesus, sent him to bless you, in turning away every one of you from his iniquities.”
Acts 3:22-
“Heaven and earth shall pass away: but my words shall not pass away.”
Mark 13:31
“being born again, not of corruptible seed, but of incorruptible, by the word of God, which liveth and abideth for ever. For All flesh is as grass, And all the glory of man as the flower of grass. The grass withereth, and the flower thereof falleth away: But the word of the Lord endureth for ever. And this is the word which by the gospel is preached unto you.”
1 Peter 1:23-25 KJV
“and that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father.”
Philippians 2:11 KJV