Martin Luther understood that God tasked the family with faith development. So he wrote what is called the Small Catechism to enable parents to teach the faith the their children. This catechism has 6 main parts- the Ten Commandments, the Lord's Prayer, the Creed, Baptism, the Lord's Supper, and Confession and Absolution.

To see how he explained these things and what we still believe today click here: https://catechism.cph.org/#