O Aisha, if I desired, then all of these mountains would be turned to gold for me. An angel came to me, his belt was bigger than the Ka'bah itself, and he asked me, 'Do you want to be a nabiyan-malika (a king-prophet) or a nabiyan-abda (a slave-prophet)?' And I chose to be a nabiyan-abda.
A separate, more weakly-chained telling of the same encounter, recounted by the Prophet ﷺ directly to Aisha RA.