Musnad Ahmad 33:1053

I read to Abd al-Rahman: Malik; and it was narrated to us by Ishaq, who said: Malik informed us, from Ja'far ibn Muhammad, from his father, that Jabir ibn Abd Allah said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, when he went out from the mosque and he intended to go to al-Safa, and he was saying: "We begin with that which Allah began with."