Musnad Ahmad 534:4

Yahya ibn Hammad narrated to us, Shu'bah informed us, from Yazid ibn Khumayr, from Ibn 'Abdullah ibn Busr, from his father, that the Messenger of Allah (peace and blessings of Allah be upon him) alighted, and they mentioned *watbah* (a type of food), food, and drink. He began eating dates and placing the pits on the back of his two fingers, then he threw them. Then he stood up and mounted a white mule of his. I took hold of its bridle and said, "O Prophet of Allah, supplicate to Allah for us." He said: "O Allah, bless them in what You have provided for them, forgive them, and have mercy upon them."