Charles Ellicott Commentary Ezekiel 4:7

"And thou shalt set thy face toward the siege of Jerusalem, with thine arm uncovered; and thou shalt prophesy against it." — Ezekiel 4:7 (ASV)

Set your face is a common Scriptural expression for any steadfast purpose. (Leviticus 20:3; Leviticus 20:5–6; Leviticus 26:17; 2 Chronicles 20:3 (marginal note), and others.) It is a particularly favorite phrase with Ezekiel (Ezekiel 15:7; Ezekiel 20:46, and others).

Here, this steadfastness of purpose was to be exercised toward the siege of Jerusalem; there would be no relenting in this matter—God’s purpose of judgment would surely be fulfilled. Further symbolism to the same effect is added, Your arm shall be uncovered, withdrawn from the loose sleeve of the Eastern robe, and made ready for battle. (Compare Isaiah 52:10.) Moreover, he is to prophesy against it, doubtless by words suited to his actions.