Musnad Ahmad 30:472

Abu Kamil narrated to us, Ibrahim narrated to us, Ibn Shihab narrated to us, from Sa'id ibn al-Musayyib, from Abu Hurayrah, who said: The Prophet, peace and blessings of Allah be upon him, was asked: "Which deeds are best?" He said: "Faith in Allah and His Messenger." It was said: "Then what?" He said: "Then Jihad in the way of Allah." It was said: "Then what?" He said: "Then an accepted Hajj."