Cain

According to verse 17, Cain had a wife, a son, and even began building a city. But this is not a contradiction. The land of Nod in verse 16, means land of wandering. Clearly then, the author did not forget that Cain was to be a vagabond and wanderer who was apparently not precluded from having a family and building a city, and the context may have been a wanderer for most of his life, having built the city only a long time later, or that his city was in a far away land, and was secluded and Cain (and his family) was a wanderer in the sense that he had to go away from everyone (and he certainly would have wandered before building the city). Whatever is the case, the text doesn’t necessitate an error, and it’s unlikely the author would have forgotten that Cain was to be a wanderer the very next verse after mentioning his having gone to the Land of Wandering (Nod), so in his contextual view (it’s unlikely verse 17 was written by a different, later author, since it serves no purpose, and he would have changed the preceding verses that say Cain was a wanderer), apparently for the author’s language and culture and what he meant by the text, building a city and having a family was not in conflict with the status of a vagabond and wanderer.