Reading Exodus brings you to the details of the Tabernacle, the place of Worship for Israel. One is struck by the elaborate details all through the reading. Great care is taken with the layout of the tabernacle, the various pieces of furniture placed in it, the robes and ornaments of the priests, the incense and so forth. To the 21st century reader it is nearly oppressive. You find yourself asking, “Is all this necessary?”
But notice the contrast between the worship that the people made up for themselves in Exodus 32. Moses was away on the Mountain and the people were restless. So Aaron asks for their gold jewelry, tosses it in the fire and out comes a golden calf. (or that is what he later tries to say to Moses). This is your god, he says, who brought you here. And the people are overjoyed to have a god they can see, so they rise up in celebration and in sensual enjoyment.
Then follows about 8 chapters of details on the tabernacle. God remains invisible, though there are symbols with meaning all around (light, bread, incense, gems, curtains, bells and so forth). Only the appointed priest can enter the place of God’s presence, and only with great preparations of sacrifice, washing and robing.
One lesson must be that our “spontaneous” worship lacks something. when we say, “I can worship God by taking a hike or paddling my canoe through nature, not when I go to church.” That is true to a degree, but do we learn something in church (confession, assurance, adoration, sermon, communion, prayer) that is lacking when we are left to our own?
Also, Aaron who made the golden calf is also the first priest. How could that happen? Perhaps the point of it all is mercy.