Musnad Ahmad 22:4

Yahya narrated to us, from Ibn Jurayj, Abu al-Zubayr informed me, Abu Ma'bad informed me, he said: I heard Ibn Abbas informing about al-Fadl, he said: The Messenger of Allah (peace and blessings of Allah be upon him) said on the evening of Arafah and the morning of Jam' (Muzdalifah) to the people when we departed: "Upon you is tranquility," while he was restraining his she-camel. Until when he entered Mina, when he descended into Muhassir, he said: "You must use the pebbles of *khadhf* (small pebbles thrown with the fingers) with which the Jamrah is pelted." And the Messenger of Allah (peace and blessings of Allah be upon him) was gesturing with his hand just as a person throws. Rawh and al-Barsani said: "The evening of Arafah, and the morning of Jam'," and they both said: "When they departed."