Jamieson, Fausset and Brown on Jeremiah 37:12

12. Benjamin--to his own town, Anathoth.

to separate himself--Margin translates, "to slip away," from a Hebrew root, "to be smooth," so, to slip away as a slippery thing that cannot be held. But it is not likely the prophet of God would flee in a dishonorable way; and "in the midst of the people" rather implies open departure along with others, than clandestine slipping away by mixing with the crowd of departing people. Rather, it means, to separate himself, or to divide his place of residence, so as to live partly here, partly there, without fixed habitation, going to and fro among the people [Ludovicus De Dieu]. Maurer translates, "to take his portion thence," to realize the produce of his property in Anathoth [Henderson], or to take possession of the land which he bought from Hanameel [Maurer].