“Our starting point must be Jer.18:7-10. Here it is stated categorically that all national prophecy is conditional. It is based on conditions in existence at the time of the prophecy, and if these are changed, then the prophecy ceases to be in force. The most obvious example of this is Jonah’s prophecy to Nineveh. Not only was it not fulfilled, but quite obviously Jonah did not expect it to be (4:2).
Except where a promise is confirmed by God’s oath (Gen. 22:16; Psa. 105:9; Heb. 6:13) we are safe in concluding that every statement of God about the future has some element of the conditional in it, something ancient Israel was as unwilling to believe as we are.
Where the prophecy is concerned mainly with the doom or prosperity of an individual or of a people, a change of behaviour can annul the prophecy. This explains the apparent smugness of Hezekiah’s answer to Isaiah (Isa. 39:8), when the latter foretold the Babylonian captivity. He knew that by living Godfearing lives his descendants could postpone the judgment indefinitely.
Something will have happened both in Tyre and in Egypt, and it may be in Babylon, to cause the doom uttered [in Ezekiel 25] not to go into effect, and for Ezekiel this was so obvious that neither apology nor explanation was necessary.
Where, however, the prophecy is one of God’s purposes of blessing to mankind, the element of condition is merely one of time and manner, not of substance. For example, had David’s successors walked in his ways, God’s promise (II Sam. 7:12-16) to David would have been fulfilled in all its details, Their sin led to the fall of the royal house, but the essential portion of the promise was fulfitled in Christ.
If we could grasp this clearly, it would clear away much false exegesis on prophetic Scripture.”
-H.L. Ellison, Ezekiel: The Man and His Message, 103.