James Burgess records Joseph Smith teaching that the Constitution will "hang by a brittle thread" but the Saints will save it.
James Burgess Journal, May 1843, 1818–1904, 297, MS1858, Church History Library
In the month of May 1843. Several miles east of Nauvoo. The Nauvoo Legion was on parade and review. At the close of which Joseph Smith made some remarks upon our condition as a people and upon our future prospects contrasting our present condition with our past trials and persecutions by the hands of our enemies. Also upon the constitution and government of the United States stating that the time would come when the Constitution and Government would hang by a brittle thread and would be ready to fall into other hands but this people the Latter day Saints will step forth and save it. General Scott and part of his staff on the American Army was present on the occasion. I James Burgess was present and testify to the above
This journal begins in 1841, but this particular entry is near the very end of the journal, and the handwriting is unsteady when compared to the majority of the journal. It was likely written decades later and added to the end of the book.