The Church is deeply in debt, and President Lorenzo Snow suddenly feels that the Lord wants him to travel to the city of St. George, though he does not know why. When he arrives, he begins preaching in the church, still not knowing why he has been called there or what he is to say. Suddenly, he is inspired to preach on the importance of paying a full tithe. St. George has been suffering from a devastating drought, and Snow promises that if the people will pay a full tithe, God will make it rain. He instructs them to plant their fields, promising that the drought will end and they will have a harvest "this very season." Trusting that Snow is a prophet, the people follow these instructions, but months go by with no rain in sight. Both the people and prophet are troubled but do not lose faith -- and, a few months after Snow's visit to St. George, it rains and the drought finally ends.
And this is from the conclusion to E. Jay Bell's article "The Windows of Heaven Revisited: The 1899 Tithing Reformation" in the Journal of Mormon History Vol. 20, No. 1, 1994.
What can be said, in summary, about the strong image prevalent in the minds of many members that a renewed emphasis on tithing began in a historical event: Lorenzo Snow's prophetic promise to the struggling Saints in St. George that the windows of heaven would open metaphorically in blessing and literally in breaking the drought if they would pay their tithing? The evidence is conclusive that Lorenzo Snow indeed received a revelation about the importance of renewed emphasis on tithing and made inspired promises churchwide about the continued existence of the Church if the Saints of his day would obey this principle.
However, despite numerous opportunities to remind the people that it would rain if they paid their tithing and despite great motivation to do so until drought cycle broke in 1902, neither the ecclesiastical leaders in St. George Stake nor General Authorities made such reminders. Available contemporary evidence, including LeRoy Snow's own accounts, provide no evidence of such a promise, yet it was LeRoy's triple accounts, published some thirty-five years after witnessing the event, which created the link between rain and tithing. Perhaps his memory was faulty and he did not consult his own records; or perhaps a fuller account lies in records not yet available to researchers..
So Lorenzo Snow did not promise that the drought would end if people paid tithing, and the drought did not in fact end until a year after Snow's death and three years after his visit to St. George.
What's left of the story, then? The Church was in debt, Snow traveled around preaching tithing, people paid more tithing, and the Church got out of debt. Not much drama in that! Overall, though, I'm a bit relieved that the film, with its offensive quid-pro-quo premise, is only a work of fiction.
I am a firm believer in the reality of miracles. Nevertheless, the story of The Windows of Heaven is a reminder of how easily "miracles" can work their way into a narrative, even in cases where there is apparently no conscious desire to deceive.
