EZK 46:12

12 When the king gives an offering that is not required, either one to be completely burned [on the altar] or an offering to maintain fellowship with [me, Yahweh, the entryway on the east side of the courtyard] must be opened for him. Then he must present those offerings like he does on the Sabbath days. Then he must go out, and after he goes out, the entryway must be shut.