Westminster Shorter Catechism

Q. 61. What is forbidden in the fourth commandment?

A. The fourth commandment forbiddeth the omission or careless performance of the duties required, and the profaning the day by idleness, or doing that which is in itself sinful, or by unnecessary thoughts, words, or works, about our worldly employments or recreations.

Q. 62. What are the reasons annexed to the fourth commandment?

A. The reasons annexed to the fourth commandment are, God's allowing us six days of the week for our own employments, his challenging a special propriety in the seventh, his own example, and his blessing the sabbath day.