(More about Mormonism and Christianity at http://www.mormontopics.org/eng/christ)
What is the priesthood? The priesthood is the privilege, authority, and duty to act on behalf of God. It is offered to all worthy men in the Church. The priesthood is utilized in many different capacities.
Are there different types of priesthood? There are two branches of the priesthood in the LDS Church: the Aaronic Priesthood and the Melchizedek Priesthood. The Aaronic Priesthood is sometimes referred to as the "Lesser" Priesthood, not because it is less important, but because it is a preparatory priesthood for the Melchizedek, or "Higher" Priesthood. Those holding the Aaronic Priesthood have the authority to prepare, bless, and pass the sacrament, and baptize those joining the Church. They have the responsibility to ensure the sanctity and reverence of the Church, and to be peacemakers.
When a man receives the authority of the Melchizedek Priesthood (usually in his late teens) he does not lose the Aaronic Priesthood. Melchizedek Priesthood holders hold the Aaronic Priesthood as well, and are given more duties and authority. The Melchizedek Priesthood authorizes a man to confer the Holy Ghost upon a member after baptism. They may give special blessings to heal the sick and afflicted, give other men the power of the priesthood, perform many ordinances in the temple and even seal husbands and wives, parents and children for all eternity, allowing righteous families to be together forever.
Who benefits from the priesthood? The priesthood is a sacred gift from God, which benefits everyone, not just the men who hold and use it, but also the men and women they serve. The priesthood is God's way of preparing mankind to become something more, strive for something greater, and to exercise our will by submitting to His and putting all faith in Him.
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