3 Moreover take thou unto thee an iron pan, and set it for a wall of iron between thee and the city: and set thy face against it, and it shall be besieged, and thou shalt lay siege against it. This shall be a sign to the house of Israel.
An iron plate, which is meant to be the image of the wall between the prophet and the city, represents the anger of God in all its fullness, which does not diminish as a result of any prayers, nor does it bend toward mercy in any way.
(Ver. 3.) And you shall take for yourself an iron pan: and you shall place it as an iron wall between you and the city, and you shall set your face against it, and it shall be for a siege, and you shall surround it. This is a sign for the house of Israel. What we previously said, both the prophet himself and the description of the side, the fortifications, the rampart, and the battering rams surrounding (or surrounding), as a sign before the siege of Jerusalem, is now stated more clearly, after many things that are in the middle: The sign for the house of Israel is an iron pan, which is placed as a wall between the prophet and the city, demonstrating the great wrath of God, which shall not be tired by any prayers, nor be inclined to mercy. For just as iron tames all metals and there is nothing harder than it, so the incredible crimes of Jerusalem, by their own fault, made the gentle nature of God to be the harshest. The frying pan is also said to be a wall placed in the middle between the people and God, so as to show that the whole multitude is to be broken in a short time and reduced to nothing. However, the sternness of the face towards the city is an indication of severity, according to what we read elsewhere: The face of the Lord is against those who do evil, to cut off the memory of them from the earth (Psalm 34:16).
Why is it that the prophet places this pan between himself and the city as a wall of iron? The meaning is that this strong zeal now at work in the mind of the teacher will be a witness on the day of the last judgment between him and the soul for which he is zealous against vices. Even if he who is taught is unwilling to hear, yet the teacher, by reason of the zeal that he exhibits, will not be answerable for the negligence of his hearers.
The teacher lays siege against the soul of the hearer when he proclaims that traps of temptations may be laid in everything that happens in this life, so that when the mind is everywhere fearful, everywhere circumspect, the more timidly it lives, the more vigilant it will be.
Just as the house of Israel physically underwent a siege, so each soul that now begins to serve almighty God perceives the traps the evil spirits are laying siege to it.
[AD 420] Jerome on Ezekiel 4:3