Charles Ellicott Commentary Ezekiel 46:12

"And when the prince shall prepare a freewill-offering, a burnt-offering or peace-offerings as a freewill-offering unto Jehovah, one shall open for him the gate that looketh toward the east; and he shall prepare his burnt-offering and his peace-offerings, as he doth on the sabbath day: then he shall go forth; and after his going forth one shall shut the gate." — Ezekiel 46:12 (ASV)

A voluntary burnt offering. —One case in which the prince might present a sacrifice has not yet been provided for. He might offer, like any of the people, a voluntary sacrifice at any time, either a burnt offering or a peace offering. In this case, he is still to enter by the east gate; but the gate, instead of standing open until evening, as on the Sabbaths and new moons, is to be immediately shut as soon as he retires after the completion of the sacrifice.