Does Jesus have to be a King in order to be a valid Priest and Sacrifice?
Since Jesus is not to be a priest in the levitical order, He need not be from the tribe of Levi
In the sacrifice of the New and Eternal covenant, Jesus does not merely perfect the priesthood, but bestows it upon us.
Yes, it is through the death of Christ we are made clean, our sin atoned for. This is priestly imagery.
He has a sacrifice, as every priesthood must have; but His Victim is of singular and outstanding value; Christ is the true King of Justice. Therefore, Jesus is a superior High Priest because Melchizedek’s order is permanent. The doctrine of the priesthood of all believers states that all believers in Christ share in his priestly status, eliminating any special classes. He will be a priest-king like Melchizedek, ruling in Jerusalem. Jesus saw himself as David’s lord and priest-king.