The Melchizedek priesthood is the primary office in the government of the Kingdom of God where you are walking in the position of being a king, priest and firstborn. Yeshua is the Melchizedek priest of the heavenly tabernacle.  From Adam to Jacob, there were 12 Melchizedek priests on the earth.  A Melchizedek priest has a responsibility to be faithful to the office by living according to the Torah and to teach the Torah to others. You could lose your position because of unfaithfulness and it could be sold or given to another.  At mount Sinai, the entire nation of Israel were offered the Melchizedek priesthood (Exodus 19:5-6). Because of the sin of the golden calf, this did not happen. Instead, the individual offices (king, priest, firstborn) were split within Jacob’s family being given to Judah (kingship), Levi (priests) and Joseph (firstborn). Through the new covenant, Yeshua has made all believers in Him a king, priest and firstborn.  By being faithful to Yeshua and His Torah, His Bride will be Melchizedek priests forever in the New Jerusalem.