“How often have I lifted my heart in gratitude for the two missionaries who did not stop at the first floor! How often my heart reaches out in appreciation for their faith and work. How often have I given thanks that they kept going—even to the fourth floor, last door.” — President Dieter F. Uchtdorf
President Dieter F. Uchtdorf

President Dieter F. Uchtdorf, Second Counselor in the First Presidency
Fourth Floor, Last Door · October 2016 general conference
Especially for missionaries