In the twentieth chapter of Exodus we find that Moses has been given the Ten Commandments. We mentioned a while back that the admonition to "have no other gods before Me" is an expression of God's revulsion at the very idea of seeing an idol in our lives.
As we read further in the chapter we see instructions to Moses for the building of the altar of sacrifice (verses 24-26) along with instructions for comportment of the priests in utilizing the altar.
The altar is to be made of earth, said the Lord. But if you will build it of stone, do not lay any tool upon the stone, for that pollutes the stone. Now why, I wondered, did God direct an earthen altar and yet grant permission for it to be built of stone? I think it is this. The People at this time were traversing, or more properly, wandering the desert. Likely there were places with rocky earth where gathering stones is more practical than attempting to dig. So far, so good.
But then why the prohibition against the use of tools? I think this hearkens back to the "graven images" commandment. Use no tools lest you become artistic, polish the stone, carve it or engrave it and then admire your handiwork which in essence makes the worship not of God, but of the self.
Now Moses was instructed not to allow the priests to go up to the altar by way of a stair, or steps. Now why is that? Understand that all the peoples, including the priests, were doubtless clad in loose-fitting flowing garments, Climbing stairs in the desert breezes might well lead to the catastrophe of a priest's "nakedness being uncovered." This would certainly not be conducive to worship, God did not want to see that nor did He want the people to see it. So, no stairs.
Whoa, you might be thinking. Later when God gave instructions for the building of the temple he was very specific in ordering a very tall altar. So how was it accessed? Some think by way of a ramp, but I think if we read further in the Book of Exodus we will find that God ordered a covering of modesty for the priests: linen breeches to extend from the loins to the thigh. (Chapter 28, only one of the many linen items the priests were to wear. Possibly steps were allowed after the appropriate clothing of the priests.
Also, one might ask, "What about the ornate and artistic construct of the temple, given these directions for avoiding human art work?" I think the answer is this. God gave very specific blueprints for the temple, gave specific talents to the artisans, and the construct was an act of obedience to the Lord. Well, that is what I think.
And now. Given our salvation and an intercessor in the Lord Jesus Christ we are under the admonition to be always in worship wherever we are. "Rejoice evermore. Pray without ceasing." (I Thessalonians 5:16,17)