What is the true purpose of the Sabbath? God's instruction about the Sabbath is contained in general principles that we are to apply properly. To do this, we have to understand its purpose.
From the beginning of His ministry, Jesus instructs us on how to live His way of life using these principles. The Sabbath is so significant that His ministry formally began on one and ended on a preparation day for another. In His inaugural sermon (Luke 4:16-19), He spells out His work: setting people free from captivity. He specifically mentions revealing His truth to the poor (that is, the weak), brokenhearted, captives, blind, and oppressed (see Isaiah 61:1-2).
The Sabbath—which, He says in Mark 2:27, "was made for man"—is a key element in this work of delivering people from oppression. God established His Sabbath law, including the weekly and annual Sabbaths, to prepare a people to come out of and stay out of spiritual slavery. Each Sabbath reminds Christians that God is their Liberator, and by keeping it, they show that they are free and want to remain free.
We need to recognize that the blind man's life was not in immediate danger, but the liberating healing Jesus performed was done to one who was chronically ill. Spiritually, we are the same, beset by lingering sins. God provides the Sabbath to free us from the chronic problems caused by the desires of our human nature.
Martin G. Collins
The Miracles of Jesus Christ: Healing a Man Born Blind (Part Two)