The regulation of migration to and from Israel had in view the object of maintaining the settlement of the Land. One must not emigrate unless the necessaries of life reach the price of a "sela" (two common shekels) for a double se'ah-measure of wheat, and unless they are difficult to obtain even then. A person may compel his or her spouse, under pain of divorce, to go with them and settle in Israel, which is not true for any other travel.