Albert Barnes Commentary Ezekiel 44:3

"As for the prince, he shall sit therein as prince to eat bread before Jehovah; he shall enter by the way of the porch of the gate, and shall go out by the way of the same." — Ezekiel 44:3 (ASV)

The prince – Foretold under the name of David (Ezekiel 34:24). The rabbis understood this to be the Messiah.

To eat bread – See (Leviticus 2:3) and (Leviticus 24:9). According to the old Law, these feasts belonged only to the priests; none of the rest of the congregation, not even the king, might partake of them.

The new system gives to the “prince” a privilege which he did not previously possess. As the representative of the Messiah, the prince now stands in a higher position than the kings of old. “To eat bread” may also include participation in the animals sacrificed, portions of which were reserved for those of the people who offered them.