Sayyiduna Abu Dharr (may Allah be pleased with him) narrates that I asked, "O Messenger of Allah, which mosque was built first on the earth?" The Prophet (peace and blessings be upon him) replied: "Al-Masjid al-Haram." I asked, "Then which was built after that?" The Prophet (peace and blessings be upon him) replied: "Al-Masjid al-Aqsa." I asked, "What was the time span between the two?" The Prophet (peace and blessings be upon him) replied: "Forty years. Then, wherever you may be when the time for prayer comes, perform the prayer there, for that is a mosque." This is the hadith of Abu Mu'awiyah (all the teachers of the Imam have narrated the hadith with the same meaning). Imam Abu Bakr (may Allah have mercy on him) says that the hadiths of the Prophet (peace and blessings be upon him) stating, "The whole earth has been made a mosque and a means of purification for us," are related to this chapter.