Heb.5:5,6 – So also, Christ was not self-appointed and did not glorify himself by becoming a high priest, but God called and glorified him! For the Father said to him, “You are my favored Son. Today I have fathered you.” And in another Scripture he says about this new priestly order, “You are a Priest like Melchizedek, a King-Priest forever!”
Everything about the Old Testament was temporary and subject to failure. From the sinful nature of the priests to the backsliding off the kings the Old Testament reeks of human’s inability to walk with God. Our intentions seem good but things just don’t seem to work out. Christ is able to complete the role of eternal mediator and priest because He is both God and man. His humanity allows Him to relate to us and us with Him. His deity gives Him total access to the heavenly realm, after all He has been there with the Father from eternity. Because of the mystery of God becoming man we now have an eternal priest who sits at the throne of power representing us for eternity as a man. Here is how Matthew Henry describes this.
“God the Father appointed him a priest of a higher order than that of Aaron. The priesthood of Aaron was to be but temporary; the priesthood of Christ was to be perpetual: the priesthood of Aaron was to be successive, descending from the fathers to the children; the priesthood of Christ, after the order of Melchisedec, was to be personal, and the high priest immortal as to his office, without descent, having neither beginning of days nor end of life, as it is more largely described in the seventh chapter, and will be opened there. Christ is here preferred to Aaron in the holiness of his person. Other priests were to offer up sacrifices, as for the sins of others, so for themselves. But Christ needed not to offer for sins for himself, for he had done no violence, neither was there any deceit in his mouth.”
What a powerful mystery, Christ was born on earth as a man without a human Father. He has been begotten from eternity without a mother. He is God and He is man. The greatest of all news, he lives forever to represent me and pray for me before the Father in heaven. I don’t think it can get any better than that.