That ye may know that I am the Lord that doth sanctify you. Ex. 31:13.
Some believe that sanctification is something that will happen to you just before you die, but that is not so. Sanctification is the work of a lifetime, just as much as breathing is the work of a lifetime. At the very beginning of your acceptance of the plan of salvation, your sanctification took place. Sanctification in Bible usage is a finished, completed work, as well as a progressive work. It means that one is set aside for a holy purpose. It is God that does it in the beginning, and in the ongoing process as well. He says, "I am the Lord that doth sanctify you." He is active in your everyday life, and has promised to carry forward the work He has started.
The Sabbath is a symbol of sanctification. The Sabbath is a reminder of our liberation from bondage. It is a reminder that life has meaning now. It is a reminder that God is active in our everyday life, carrying forward His work of growth, of holy use, of purpose for our lives. The Sabbath is all of that and much more. The Sabbath was designed for spiritual growth and refreshment and rest. When Adam and Eve were created, their first whole day was a day of rest. Were they tired, so soon after being created? No, God wanted them to be reminded of the fact that the best man could do when he came on the scene was to rest, for the works were already done.
This is what Hebrews 4 is all about. "Let us therefore fear, lest, a promise being left us of entering into his rest, any of you should seem to come short of it." "For we which have believed do enter into rest." "For he spake in a certain place of the seventh day on this wise, And God did rest the seventh day from all his works." "For he that is entered into his rest, he also hath ceased from his own works, as God did from his." "Let us labour therefore to enter into that rest."
How do you enter into rest? By believing or trusting in the Lord Jesus Christ. And we must labor to enter into that rest. Isn't that a strange phrase? Have you ever labored to rest? Where is the labor? Jesus said, "Come unto me, all ye that labour and are heavy laden, and I will give you rest" (Matt. 11:28). The labor is in coming to Him for rest. Our labor is not to fight the devil and sin and temptation. God gave us the Sabbath to remind us of this fact.