Musnad Ahmad 30:1611

Abu Salamah narrated to us, 'Abd al-'Aziz ibn Muhammad narrated to us, from Thawr ibn Zayd, from Abu al-Ghayth, from Abu Hurayrah, that the Messenger of Allah, peace and blessings of Allah be upon him, said: "The one who strives for the widow and the needy is like the mujahid in the way of Allah, or like the one who stands in prayer at night and fasts during the day."