Here are a few words of wisdom by Tim Keller on our need for rest.
In the Bible, Sabbath rest means to cease regularly from and to enjoy the results of your work. It provides balance: ‘Six days you shall labor and do all your work, but the seventh day is a Sabbath to the Lord your God’ (Exodus 20:9–10). Although Sabbath rest receives a much smaller amount of time than work, it is a necessary counterbalance so that the rest of your work can be good and beneficial.
God liberated his people when they were slaves in Egypt, and in Deuteronomy 5:12–15, God ties the Sabbath to freedom from slavery. Anyone who overworks is really a slave. Anyone who cannot rest from work is a slave – to a need for success, to a materialistic culture, to exploitative employers, to parental expectations, or to all of the above. These slave masters will abuse you if you are not disciplined in the practice of Sabbath rest. Sabbath is a declaration of freedom.
Thus Sabbath is about more than external rest of the body; it is about inner rest of the soul. We need rest from the anxiety and strain of our overwork, which is really an attempt to justify ourselves—to gain the money or the status or the reputation we think we have to have. Avoiding overwork requires deep rest in Christ’s finished work for your salvation (Hebrews 4:1–10). Only then will you be able to ‘walk away’ regularly from your vocational work and rest.
Sabbath is the key to getting this balance, and Jesus identifies himself as the Lord of the Sabbath (Mark 2:27– 28) – the Lord of Rest! Jesus urges us, ‘Come to me, all you who are weary and burdened, and I will give you rest. Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls’ (Matthew 11:28–29). One of the great blessings of the gospel is that he gives you rest that no one else will.