So often in our busy lives we neglect to take a day off. We wear not taking a day off as a badge of pride. Many of us or our friends work two or three jobs. One of these might be a small business on the side, and nearly any small business takes additional time to manage and grow.
What then is the value in having a day off to rest?
First, the Lord commands it. God created you, He knows you need rest.
Scripture says, before the Law of Moses, "on the seventh day God rested from all his work." As shocking as it may sound, the example of taking a 7th day off to rest is in the first few chapters of the Bible as a pattern. We're not stronger than God, so we should take it seriously. Later, this was codified into the Law for Israel to use. But the idea of a day of transcends the Law of Moses.
Scripture also relays to us, we look forward to a Sabbath rest, aka, a time of stopping. Hebrews 4:9-10 hints at its value. It's brought up because we should use it, the day off that is, and such a day off serves as a type of a future rest to talk of for Paul or Barnabas there.
Second, you need to catch up. If you are always going, you are going to forget things. It may be taking time for friends or family. Your parents or good friends may never hear from you. A day off gives your brain rest to figure out things you may have missed in other busy days. You'll benefit.
Third, your physical body and mind need a routine break. It's best not to do the same thing each day of the week, especially for your job. There's wisdom in this.
Fourth, a day off is a time to worship. You will be able to make special time to worship the Lord. That is worth it as you walk as a follower of Jesus Christ.
Blessings to you!