The Catechesis (teaching) from the Book of Common Prayer explains the importance of prayer:

Q. What is the duty of all Christians? 

A. The duty of all Christians is to follow Christ; to come together week by week for corporate worship; and to work, pray, and give for the spread of the kingdom of God.

Q. What is prayer? 

A. Prayer is responding to God, by thought and by deeds, with or without words.