Heavenly Father has given men the authority to do His work on earth. This authority is called the priesthood. Boys who are at least 12 years old can hold the Aaronic Priesthood. Men who are 18 years old can hold the Melchizedek Priesthood. Priesthood holders can bless and pass the sacrament, collect fast offerings, baptize, give priesthood blessings, and administer the gift of the Holy Ghost. All priesthood holders are interviewed by Church leaders before they are ordained to make sure they are worthy to use Heavenly Father’s sacred power.
Members of the Church can be called to serve in their ward or branch. When a bishop needs to fill a calling in his ward, he ponders and prays about who should be called. When he receives confirmation from Heavenly Father that the person is the right one for the calling, that person is called and set apart by priesthood authority.