What was the power of Melchizedek?

What was the power of Melchizedek? ’Twas not the Priesthood of Aaron which administers in outward ordinances, and the offering of sacrifices. Those holding the fulness of the Melchizedek Priesthood are kings and priests of the Most High God, holding the keys of power and blessings. In fact, that Priesthood is a perfect law of theocracy, and stands as God to give laws to the people, administering endless lives to the sons and daughters of Adam.
Author/Source: Joseph Smith, TofTPJS PG. 322