It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that on the occasion of the Day of Arafah, Sayyiduna Usamah bin Zaid (may Allah be pleased with him) was riding behind the Prophet (peace and blessings be upon him). The Prophet (peace and blessings be upon him) entered a valley, dismounted there, poured water, performed ablution, then mounted again and did not pray.