The document provides a list of 20 things that the author believes children should know about God, humanity, Jesus, and the sacraments before receiving communion for the first time. The list includes basics such as: there is one God in three persons; God created everything; Jesus is both God and man; and in communion one receives the body and blood of Christ. The author explains that knowing these concepts will help children understand what they are doing when receiving communion and mean what they say. The document also provides context for some of the concepts on the list.