Bible Notes Online - Ezekiel 42 - ESV
Commentary

v1-14: The building for the priests, in 41.12. They had a place to eat the offerings, to store their special clothes. Their garments and their behaviour must reflect the holiness of God.

As in the original instructions in Leviticus, priests would eat sin offerings and guilt offerings. Here they are described as most holy offerings. It seems almost unnecessary to say this, but it continues Ezekiel’s emphasis of holiness. Everything about this vision is about holiness.

v15-20: The principle of separation, keeping the holy from the common, see 40.5; 44.23. There was an inner, holy, area of 500 rods square.