Ezekiel 44:5

‘And Yahweh said to me, “Son of man, set your heart on, and behold with your eyes, and hear with your ears, all that I say to you concerning all the ordinances of the house of Yahweh, and all its laws. And set your heart on the entering in of the house, with every going forth from the sanctuary.” '

He was now told by God Himself to lay down under God's instruction all that was to be done in the sanctuary which God would cause to be built on earth which to some small extent would mirror the heavenly sanctuary, and who it should be done by. He would declare who could enter where, and who would proceed from where. He was to regulate the whole pattern of future worship in the sanctuary, as Moses had before him.