It is said that brother Joseph in his lifetime declared that the Elders of this Church should step forth at a particular time when the Constitution should be in danger, and rescue it, and save it. This may be so; but I do not recollect that he said exactly so. I believe he [Joseph] said something like this – that the time would come when the Constitution and the country would be in danger of an overthrow; and said he, If the Constitution be saved at all, it will be by the Elders of this Church. I believe this is about the language, as nearly as I can recollect it.

( Source: Journal of Discourses 6:152 – quoted by Orson Hyde )