The Lutheran sacraments are "sacred acts of divine institution".Lutherans believe that, whenever they are properly administered by the use of the physical component commanded by God along with the divine words of institution, God is, in a way specific to each sacrament, present with the Word and physical component. They teach that God earnestly offers to all who receive the sacrament forgiveness of sins and eternal salvation. They teach that God also works in the recipients to get them to accept these blessings and to increase the assurance of their possession.
In the Apology of the Augsburg Confession, sacraments are defined as:
If we define the sacraments as rites, which have the command of God and to which the promise of grace has been added, it is easy to determine what the sacraments are, properly speaking. For humanly instituted rites are not sacraments, properly speaking, because human beings do not have the authority to promise grace. Therefore signs instituted without the command of God are not sure signs of grace, even though they perhaps serve to teach or admonish the common folk.
The Sacrament of Holy Baptism is the sacrament by which one is initiated into the Christian faith. Lutherans teach that at Baptism, they receive God's promise of salvation. At the same time, they receive the faith they need to be open to God's grace. Lutherans baptize by sprinkling or pouring water on the head of the person (or infant) as the Trinitarian formula is spoken. Lutherans teach baptism to be necessary, but not absolutely necessary, for salvation. What that means is that although baptism is indeed necessary for salvation, it is, as Luther said, contempt for the sacraments that condemns, not lack of the sacraments. Therefore, one is not denied salvation merely because one may have never had the opportunity to be baptized. This is what is meant by saying that baptism is necessary—but not absolutely necessary—to salvation.
The Sacrament of the Eucharist (also called the Sacrament of the Altar, the Mass, the Lord's Supper, the Lord's Table, (Holy) Communion, the Breaking of the Bread, and the Blessed Sacrament) is where communicants eat and drink the true Body and Blood of Christ Himself, "in, with and under the forms" of the consecrated bread and wine. This Eucharistic theology is known as the Sacramental Union. (It has been called "consubstantiation", but most Lutheran theologians reject the use of this term, as it creates confusion with an earlier doctrine of the same name.)