Muhammad bin 'Ubaid al-Tanafasi محمد بن عبيد بن أبي أمية الطنافسي · The Book of ar-Ruqba

"Do not give away your property on the basis of Ruqba, for whoever gives a gift on that basis, it belongs to the one to whom he gave it."

"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.'"

"The Messenger of Allah said: 'Umra (a gift given for life) is part of the estate.'"