Hajjaj narrated from Abu Az-Zubair, from Tawus, from Ibn 'Abbas, who said:"The Messenger of Allah said: 'Umra (life-long gift) is permissible for the one to whom it is given, and Ruqba is permissible to the one to whom it is given, and the one who takes back his gift is like the one who goes back to his vomit