Musnad Ahmad 26:735

'Abd al-Razzaq narrated to us, Ma'mar informed us, from Abu Ishaq, from Abu 'Ubaydah, from Ibn Mas'ud, who said: I asked the Messenger of Allah, peace and blessings of Allah be upon him, and said: "Which deeds are best?" He said: "The prayers at their appointed times, honoring the parents, and striving (Jihad) in the way of Allah, the Almighty and Majestic."