The sacrament of Matrimony is alluded to in such passages as Ephesians 5:21-33. Again, Jesus takes the ordinary stuff of human life—falling in love, getting married, and having sex and children—and makes it a means of encounter with the Blessed Trinity through the power of the Spirit.
Marriage is, of course, a primal natural institution and we see it honored in Genesis 2. But between baptized persons, marriage is elevated to a sacrament. In the gift of mutual self-giving between man and woman, God makes the love of the Blessed Trinity himself available to us through our spouse.
In the western Church, it is the man and woman themselves who confer the sacrament on each other when they give themselves to one another in marriage. In the eastern Church, the priest confers the sacrament. But however the sacrament is celebrated, the point is that the love of man and woman, both spiritual and physical, is a doorway into the love of the Godhead. This shocks some people who think the Faith has an aversion to sex. But the reality is that, as the Eucharist is the sacrament of eating, Matrimony is, in part at least, the sacrament of sex. God likes sex. He invented it. It is a sacrament in the service of the Eucharist because the family is the first Church we encounter in our lives, the school of charity and communion in which we first encounter the love that is at the heart of the Eucharist.
Finally, the last sacrament is that of Holy Orders. We see it being celebrated in, for instance, Acts 13:1-3, when Saul and Barnabas are called by the Holy Spirit to be sent out to the world by the Church at Antioch. “After fasting and praying they laid their hands on them and sent them off.” The act of laying on of hands accompanied by a solemn prayer of consecration by a bishop—a successor of the apostles—is the core of the rite. We can see Paul and Barnabas doing the same thing in the Churches they founded in, for instance, Acts 14:23. Paul’s letters to Titus and Timothy are essentially letters of advice to two young bishops who have received Holy Orders from Paul.
There are three degrees of Holy Orders in the Church: Deacon, Priest, and Bishop.
Deacons can carry out some of the pastoral duties of the Church, but they cannot hear confessions or consecrate the Eucharist. The office was invented under the guidance of the Spirit when the apostles found they could not focus on their proper duties of preaching and celebrating the sacraments what with all the work of caring for the practical needs of the flock (Acts 6:1-7).
Priests can celebrate all the sacraments but conferral of Holy Orders, which is the work of the bishop. The work of the priesthood is to teach, sanctify, and govern. Above all, it is to serve Christ present in the Eucharist and in the people of God for whom the Eucharist is at the core of life.
Finally, bishops are successors of the apostles, charged with governing their respective dioceses as shepherds and with faithfully preaching and living the gospel through celebration of the sacraments and service to their flocks, especially to the least of these.