Mukhtasar Muslim

Sayyiduna Abu Dharr (may Allah be pleased with him) reports: I asked the Messenger of Allah (peace and blessings be upon him), "Which was the first mosque built on the earth?" He (peace be upon him) replied, "Al-Masjid al-Haram (i.e., the Ka'bah)." I asked, "Then which one?" He (peace be upon him) replied, "Al-Masjid al-Aqsa (i.e., Bayt al-Maqdis)." I asked again, "What was the time span between the two?" He (peace be upon him) replied, "Forty years." And (he said), "Wherever you may be when the time for prayer comes, perform the prayer there, for that is (also) a mosque."