||then her first husband who divorced her cannot remarry her, since she is now forbidden to him. To do so would be repulsive to God, and you must not bring immorality to the land that God your Lord is giving you as a heritage.
Lo yuchal balah harishon asher-shilchah lashuv lekachtah liheyot lo le'ishah acharey asher hutama'ah ki-to'evah hi lifney Adonay velo tachati et-ha'arets asher Adonay Eloheycha noten lecha nachalah.
(HaKethav VeHaKabbalah). Literally, 'defiled.' Or, '[The same is true] if she is defiled to him [by committing adultery]' (Rashi; Bachya; Sotah 11b).