Heidelberg Catechism – Lord’s Day 38
Q. What does God require in the fourth commandment?
A. First, that the ministry of the gospel and Christian education be maintained, and that I diligently attend church, especially on the Lord’s day, to hear the Word of God, to participate in the holy Sacraments, to call publicly upon the Lord, and to give Christian service to those in need. Second, that I cease from my evil works all the days of my life, allow the Lord to work in me through his Spirit, and thus begin in this life the eternal Sabbath.