The Lord taught that the power of the priesthood is evident in the ordinances thereof (see D&C 84:21).
Priesthood is the power to perform ordinances, physical expressions of inner commitments that signal a covenant with the Lord. For latter-day saints, there are a number of crucial ordinances, including baptism and confirmation.
The age of baptism in the Mormon Church is eight. Children younger than eight, we're taught, are not accountable for their sins and therefore have no need of baptism. For those eight and over, and for converts to the church, baptism (by immersion) is the ordinance that signifies the entering in at the gate and embarking on the path back to God. I'll speak more about the significance of baptism in another post
Confirmation follows, in which hands are laid on the person's head and that person is confirmed a member of the Church of Jesus Christ of Latter-day Saints, and given the gift of the Holy Ghost.
These ordinances, performed by those who are ordained to do so, are the beginning of one's membership in the church. There are other ordinances that may be performed: ordination to the priesthood, blessing of the sick, blessings give for comfort, the naming and blessing of children, and perhaps the most regularly performed ordinance: the sacrament.
Sacrament in the LDS Church is the ordinance in which bread and water are taken as tokens of the body and blood of Christ, reminiscent of his action at the Last Supper. The sacrament prayers teach us that these emblems should remind us of the covenants we made at baptism, and the taking of the sacrament allows members to renew those covenants. As a result, with proper repentance, we can start fresh each week in our desire to do the Lord's will in our lives.
The ordinances of the gospel are a chance for us to connect ourselves by covenant to the Lord, to become His and to signal our willingness to walk in His path.
For me, some of my most spiritual moments of my life have been while I’ve been involved in ordinances of the gospel, either receiving them or performing them. Standing in the water with my children at their baptism has been a remarkable experience each time (my seventh was baptized last year). I have felt close to them and close to the Lord, and have wondered if I have caught a glimpse in those times about how He loves me.