Question 66: How is the Sabbath to be sanctified?
Answer: One day in seven should be especially devoted to corporate worship and other spiritual exercises that restore the soul’s rest in God and zeal for His name. It should provide physical refreshment and fit one for a week of devoted service to Christ.
Question 67: What is forbidden in the fourth commandment?
Answer: The fourth commandment forbids dishonoring the Lord’s Day by actions or thoughts that divert the soul from spiritual refreshment, or deprive the body of renewed energy or distract the mind from its special Sabbath focus on the Lord.
Question 68: What are the reasons attached to the fourth commandment?
Answer: The reasons attached to the fourth commandment are, God’s creating the world in six days and resting on the seventh and his blessing the Sabbath day.
The Baptist Catechism above was adapted by John Piper. This post in its entirety can be found at http://www.desiringgod.org/articles/a-baptist-catechism