But thou, son of man, hear what I say unto thee; Be not thou rebellious like that rebellious house: open thy mouth, and eat that I give thee.
Eat that I give thee - (Jeremiah 15:16, note; Revelation 10:9-10). The idea is to possess himself fully of the message, and digest it in the mind; not literal eating, but such an appropriation of its unsavoury contents that they should become as it were part of himself, so as to impart them the more vividly to his hearers.