Baptism is the combination of water and God's Word. In Baptism the pastor pours water over the candidate's head and says, "I baptize you in the name of the Father and of the Son and of the Holy Spirit." It seems ordinary, yet because of God's command and promise it is extraordinary. Saint Paul says, "As many of you as were been baptized into Christ have put on Christ." (Galatians 3:27) Baptism goes hand in hand with faith in Christ. Faith is a gift from God as is Baptism. When we trust in our Baptism, we trust in what God has done for us through Jesus and that he chooses to give us the benefits of Jesus' death through his work of Baptism.
Baptism is the entrance into the Christian Church. The Bible calls Baptism a new birth (John 3:3, 5; Titus 3:5-6). As a newborn child needs to be clothed, fed, and cared for, so does a baptized child of God need to be cared for with God's Word and Sacraments.
Read below to learn more about Baptism from Luther's Small Catechism.
As the head of the family should teach it in a simple way to his household.
"Imagine there was a doctor somewhere who understood the art of saving people from death or, even though they died, could restore them quickly to life so that they would afterward live forever. Oh, how the world would pour in money like snow and rain. No one could find access to him because of the throng of the rich! But here in Baptism there is freely brought to everyone's door such a treasure and medicine that it utterly destroys death and preserves all people alive."
~Martin Luther, Large Catechism Part IV.