Musannaf Ibn Abi Shayba 4:37

Yazid ibn Harun narrated to us, he said: Muhammad ibn Ishaq informed us, from al-Zuhri, from Humayd ibn Abd al-Rahman, from Abu Hurayrah, from the Prophet, peace and blessings of Allah be upon him: For every person of action, there is a gate among the gates of Paradise from which they are called by that action. And for the people of fasting, there is a gate called al-Rayyan.