It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever asks by Allah, give to him; whoever seeks refuge in Allah, grant him refuge; and whoever gives you a foreleg or a trotter as a gift, accept it."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 13483