Musannaf Ibn Abi Shayba 27:882

Ishaq bin Mansur narrated to us, he said: Isra'il narrated to us, from Ibrahim bin Muhajir, from Ibrahim, from al-Aswad, who said: Ka'b met me in Bayt al-Maqdis (Jerusalem) and said: "Where have you come from?" I said: "From the Mosque of Kufa." He said: "For me to have come from where you came is more beloved to me than to give two thousand dinars in charity, placing each dinar of them into the hand of every needy person." Then he swore that it (Bayt al-Maqdis) is the center of the earth, like the bottom of a basin.