Musnad Ahmad 30:2612

Waki’ narrated to us, he said: Malik ibn Anas narrated to us, from Sumayy, from Abu Salih, from Abu Hurairah, who said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "Travel is a piece of punishment; it prevents one of you from his sleep and his food. So when one of you has fulfilled his need from his travel, let him hasten to his family."