Our doctrine of performing ordinances on behalf of the dead is unusual among the religions of the world. Many religions pray for the dead, Mormonism actively performs the same saving ordinances that the living must have. These teachings were introduced during the Nauvoo period, and baptisms for the dead were performed in the Mississippi at that time, until the basement of the Temple was complete and ordinances could be performed there. At that point Mormonism learned that these ordinances belonged in the Temple, and this understanding was captured in the following poem by William Wines Phelps, written for the dedication of the Nauvoo Temple in 1846:
The Mormon practice of proxy ordinance work has once again made its way into the news, this time involving someone no less prominent than our U.S. President’s late mother.