We usually do not think of Jesus as an Old Testament prophet because He is both God and the Savior of the world through the New Testament. The gospels are part of the New Testament canon because they show how the New Testament came into being, but the New Testament did not come into being until His death and resurrection, which are the end of the gospel narratives.
The writer of Hebrews (I believe to be Paul) makes this point, too.
1 God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets,
2 Hath in these last days spoken unto us by his Son, (KJV)
As you can see, Jesus, as the Son of God, is listed as the last Old Testament prophet. Which means that we should view the gospel narrative as the last instruction of Yahweh to the Jewish people still under the Mosaic Covenant. This is what Jesus meant when He said:
Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil. (Matt 5:17 KJV)
He completely fulfilled the requirements of the Old Testament. He did not come to fulfill the rabbinic additions of the Talmud, however. The New Testament was impossible to bring in without His total obedience to the will of the Father, which is the Spirit behind the Old Testament. Our salvation is based upon His works. Without His works, we could not be saved. Therefore, we can not understand the gospel story if we ignore the Old Testament dispensation that He lived in and closed.
All His instruction to the crowds and the disciples were a bridge between those two covenants. Until His death and resurrection, there was no experience of the regeneration in His audience. There was a temporary experience that came with the sacrificial offering of animals whose innocent blood provided a brief experience to the contrite Jew. Hence David, in Psalm 51, cries out to the Lord:
10 Create in me a clean heart, O God; and renew a right spirit within me.
11 Cast me not away from thy presence; and take not thy holy spirit from me. (KJV)
Likewise, a personal relationship with Yahweh was experienced by some even up to the time of Jesus. Consider Simeon at the Lord’s birth:
25 And, behold, there was a man in Jerusalem, whose name was Simeon; and the same man was just and devout, waiting for the consolation of Israel: and the Holy Ghost was upon him.
26 And it was revealed unto him by the Holy Ghost, that he should not see death, before he had seen the Lord’s Christ.
27 And he came by the Spirit into the temple: and when the parents brought in the child Jesus, to do for him after the custom of the law,
28 Then took he him up in his arms, and blessed God, and said,
29 Lord, now lettest thou thy servant depart in peace, according to thy word:
30 For mine eyes have seen thy salvation, (KJV)
But these were not permanent experiences. Only after the Lord’s resurrection could the Holy Spirit permanently indwell in the hearts of all believers, thus creating the new birth. For Jesus, He spoke to an audience that was partially blind about those things that could only be understood after the new birth. This is why Paul was raised up by the Lord to further clarify and explain to the infant Church the ramifications of the new life in Christ fuller.
Consider the Golden Rule. We all know it. Long before I ever became a Christian, my mother had admonished me to live by the Golden Rule, even though she does not have the new birth. Jesus gave this great statement in His Sermon on the Mount.
Therefore all things whatsoever ye would that men should do to you, do ye even so to them: for this is the law and the prophets. (Matt 7:12 KJV)
It is noteworthy that this understanding of “doing unto others as one would have others do unto us” is found in every major religion and culture of the world. While this rule was stated in the book of Leviticus in a similar fashion (Thou shalt love thy neighbor as thyself – Lev. 19:18) and was quoted by the lawyer to Jesus (Matt 22:25 and Luke 10:25), it is an expression of natural law, which any unregenerate person can understand. Jesus was speaking in terms that the unregenerate can follow in His Sermon on the Mount. The Sermon was not an instruction in the new life in Christ.
The Golden Rule for the regenerate is better stated this way: “We should do unto others as the Father does to us.” This is how Jesus lived. He said:
John 5:19 – 20
19 Then answered Jesus and said unto them, Verily, verily, I say unto you, The Son can do nothing of himself, but what he seeth the Father do: for what things soever he doeth, these also doeth the Son likewise.
20 For the Father loveth the Son, and sheweth him all things that himself doeth: and he will shew him greater works than these, that ye may marvel. (KJV)
And many more examples could be used to make the point. We have the permanent indwelling of the Father. We, too, need to be about our Father’s business.
Every believer needs to compare all that they hear regarding Christ and the Bible to what you know first hand from Christ Himself dwelling in your own heart. Read the gospels and keep in mind that they are transitional narratives. They could have just as easily been the last books of the Old Testament as well as being the first books of the New Testament. We live as Jesus lived in the gospels, who had the permanent indwelling of the Holy Spirit. He died and rose again so we could share His same great joy.