Musnad Ahmad 26:649

'Abd al-Rahman narrated to us, Sufyan narrated to us, from al-A'mash, from Abu Wa'il, from 'Abdullah, who said: "I prayed, or I stood, with the Prophet, peace and blessings of Allah be upon him, one night. He continued standing until I intended to do something bad." He said: We said: "What did you intend?" He said: "I intended to sit down and leave him."