Musnad Abu Ya'la al-Mawsili 109:117

Ibrahim narrated to us, Hammad narrated to us, from Habib al-Mu'allim, from 'Ata, from Jabir, that a man said on the day of the Conquest: "O Messenger of Allah, I vowed that if Allah grants you victory, I would pray in Bayt al-Maqdis (Jerusalem)." The Messenger of Allah, peace and blessings of Allah be upon him, said: "Pray right here." The man repeated it to the Prophet, peace and blessings of Allah be upon him, two or three times, and each time he said: "Pray right here." When he persisted with him, he said: "Then it is up to you."