"Sanctified" in Genesis 2:3 and "holy" in Exodus 20:8 are the same word in Hebrew though in different tenses. In Genesis 2, God makes the seventh day holy; in Exodus 20, He commands us to keep holy what He has already made holy. A holy God is required to make holy time, and He made no time holy other than His Sabbaths. God can make man holy, but man cannot confer holiness to the degree God does. Any other day of worship has a mere manmade holiness and is not holy as God's Sabbaths are holy. The Sabbath, then, is worthy of respect, deference, even devotion not given to other periods of time. It is set apart for sacred use because it derives from God.

The underlying implication of the usage of "holy" is difference. The verbal root literally means "to cut," "to cut out," "to separate from," or it can imply "to make a cut above," thus "to make special." A holy thing is an object that is different from that to which it is compared. In this case, the other six days are common and are given to the use and pursuit of the common, ordinary activities of life. Practically, it means that when the Sabbath arrives, we should stop doing and avoid the mundane things that make or promote turning the Sabbath into an ordinary day.

Exodus 3:1-5 provides a clear illustration of what the word "holy" implies:

Now Moses . . . came to Horeb, the mountain of God. And the Angel of the LORD appeared to him in a flame of fire from the midst of a bush. So he looked, and behold, the bush was burning with fire, but the bush was not consumed. Then Moses said, "I will now turn aside and see this great sight, why the bush does not burn." So when the LORD saw that he turned aside to look, God called to him from the midst of the bush and said, "Moses, Moses!" And he said, "Here I am." Then He said, "Do not draw near this place. Take your sandals off your feet, for the place where you stand is holy ground."

The principle shown here is what makes the Sabbath holy, different. Because God was present, Moses had to treat the ground differently, with a respect or a deference that he would not give to ordinary ground. For the called of God, this difference, this holiness, is a spiritual thing; it is not physically discerned.

Notice that, even though Moses was aware that there was something unusual about what He was observing, God had to tell him that he stood on holy ground. It is a spiritual state that cannot be physically discerned. As for the Sabbath, God puts His presence into the day for the sake of His people and His spiritual creation.

Consider the scenario Amos 3:3 presents: "Can two walk together, unless they are agreed?" If we want to be in God's presence in this special way and in agreement with Him, no other day will do. God has an appointment with us to meet with Him on a specific day, on Sabbath time. It is time, different from other time, just as an appointment time with a dentist is different from other time in one's life, as well as from another person's scheduled time.