Well, directed their building anyway. I'm one of the few in the area with some knowledge of engineering, so it falls to me. But I only do as God provides in tools, knowledge, and materials. I have faith he'll guide me to stronger, more stable earthworks this time. I simply believe it.
An engineer (well, only person with knowledge of engineering), Isaac is a devout Christian who believes that it's his faith that guides him to achieve great things. God or man, he is the person responsible for constructing the supports inside the mine.
Isaac will also happily take the The Flame Deluge Canticle from the player in exchange for a reward.
Trivia[]
Isaac's name and interactions are a reference to Walter M. Miller JR's A Canticle for Leibowitz. The titular Leibowitz is Saint Isaac Edward Leibowitz, an engineer who converted to Roman Catholicism after the nuclear holocaust and founded the Albertian Order of Leibowitz, dedicated to the preservation of knowledge.