The 139th mitzvah is that we are commanded that if one has possessions1 which are located within the walls of a city and they were sold, one has the right to redeem them only for one year. After the year has passed, the buyer becomes the full owner, and remains so even after the Jubilee Year.
The source of this mitzvah is G‑d's statement,2 "When a man sells a residential house in a walled city [he shall be able to redeem it until the end of one year after he has sold it]."
This mitzvah is known as "the law of batei arei chomah."
The details of this mitzvah are explained in tractate Erachin.3 It applies only in Eretz Yisrael.
