Commenting on the (implicitly) contingent nature of Jonah’s prophecy to the inhabitants of Nineveh, Methodist commentary Adam Clarke (1760/1762-1832) wrote the following on Jonah 3:5:
Verse 5. The people of Nineveh believed God]
They had no doubt that the threatening would be fulfilled, unless their speedy conversion prevented it; but, though not expressed, they knew that the threatening was conditional. “The promises and threatening of God, which are merely personal, either to any particular man or number of men, are always conditional, because the wisdom of God hath thought fit to make these depend on the behaviour of men.”—Dr. S. Clarke’s sermons, vol. i. (Adam Clarke, The Old Testament, volume IV: Isaiah to Malachi [1825; Repr., Nashville: Abingdon Press, 1970], 704)
Commenting on vv. 9-10, we read:
Verse 9. Who can tell if God will turn and repent] There is at least a peradventure for our salvation. God may turn towards us, change his purpose, and save us alive. While there is life there is hope; God has no pleasure in the death of sinners; he is gracious and compassionate. Himself has prescribed repentance; if we repent, and turn to him from our iniquities, who knows then whether God will not turn, &c.
Verse 10. And God saw their works] They repented, and brought forth fruits meet for repentance; works which shows that they did. (Ibid.)
Elsewhere, commenting on Jer 18:7-10, a text which explicates the contingent nature of promises and prophecies, Clarke noted:
Verses 7-10. At what instant I shall speak concerning a nation, &c.—If that nation against whom, &c.—And at what instant, &c.—If I do evil, &c.] These verses contain what may be called God’s decree y which the whole of his conduct towards man is regulated. If he purpose destruction against an offending person, if that person repent and turn to Go, he shall live and not die. If he purpose peace and salvation to him that walketh uprightly, if he turn from God to the world and sin, he shall die and not live. (Ibid., 302-3)
Here, Clarke (correctly) notes the synergy between the decree of God and the free-will actions of humans, and how God’s decree is not “immutable” or “deterministic” as Reformed theology portrays it to be.
Further Reading:
Resources on Joseph Smith's Prophecies
Jonah, Ninevah, and the contingent nature of prophecy
Is it Fair to Compare Joseph Smith with the Prophet Jonah?
An Examination and Critique of the Theological Presuppositions Underlying Reformed Theology