The levitial priesthood is for morals. The Melchezidek priesthood is for immortals.

Being cleansed by the blood of the Messiah Yeshua is referring to his immortal blood, not his mortal blood on the cross. That is why he symbolically will not drink of the blood of the new covenant until later, for it applies only to immortal beings.

The life is in the blood, as Torah explains. Thus, Eternal Life is in his immortal blood, which has power to create immortal bodies in the resurrection.

The full power of the law was offered to Israel though Moses, but they rejected Yahweh on the Mountain and asked for Moses to be a middle man, which was the cause of Israel's fall. The full law has the power to translate a human being into immortality without tasting death, but it requires an immortal being, such as Yahweh or Yahushua (Yeshua), to administer the law to unleash that power. This became impossible when Israel chose Moses, a human, to speak to them, instead of hearing directly from Yahweh face to face.

When Yahushua returns as the resurrected Messiah Ben David, He will build a temple (Ezekiel 40 to 48) and teach mortals about the power of immortality through full repentance. They will overcome death by the power of his immortal blood.

Christianity has misunderstood what the New Covenant is and how it relates to the Levitical priesthood and the first covenant. The first covenant teaches one to discipline the flesh as mortal, leading one into life within the Melchizedik priesthood and the New Covenant of the Messiah.
Jeremiah 30:34 is fulfilled in the resurrection. Then all will know Yahweh from the least to the greatest, and no one will need to argue and teach one another about him. With resurrected and immortal bodies, He will speak to us directly and we will then see clearly.

The two priesthoods are all one everlasting covenant--one priesthood for mortals and one for immortals. This is explained very clearly in the book of Hebrews. The priesthood is defined by the flesh of the high priest, whether he is mortal or immortal. Indeed, it even explains when the Levitical priesthood ends in Heb 9:10. The fleshly ordinances are to remain until the time of restoration. The Greek word is mistranslated as reformation. Restoration is correct. The word literally means when a broken bone is made straight. It is referring to the resurrection when the broken and dying human flesh is corrected and made straight again, like it was when Adam was created. Therefore, the levitical priesthood and its laws are to remain until the last human being is made into an immortal person. The earth will be changed into "new earth" without death in it, an immortal one, and then we will live in the "new" covenant designed for that kind of immortal race.