Jon visits Sam in Castle Black's subterranean library. Sam was sent to find maps for Commander Mormont and accidentally pulled an all-nighter as he got caught up in the minute details.
En route to bringing Mormont the maps, Jon and Sam talk with Donal, Castle Black's armorer. They discuss the growing roster of kings down south.
After handing Mormont the maps, Sam leaves, and Jon and the commander discuss Maester Aemon.
Aemon, it turns out, was offered the throne once as a member of the Targaryen family. He refused, as his vows required him to serve, not to rule, so instead Aemon's brother, Aegon V, took the throne. This eventually led to the Mad King taking the throne, so… wait… Is this a good thing?
Mormont points out a similarity between Jon and Aemon's royal brethren.
Like Aemon, Jon swears to keep his vows—words we are sure will in no way come back to haunt him.