Narrated Abu Dhaar: I said, "O Allah's Apostle! Which mosque was built first?" He replied, "Al-Masjid-ul-Haram." I asked, "Which (was built) next?" He replied, "Al-Masjid-ul-Aqs-a (i.e. Jerusalem)." I asked, "What was the period in between them?" He replied, "Forty (years)." He then added, "Wherever the time for the prayer comes upon you, perform the prayer, for all the earth is a place of worshipping for you."

Narrated `Urwa's father: Aisha said, "I borrowed a necklace from Asma' and it was lost. So Allah's Apostle sent a man to search for it and he found it. Then the time of the prayer became due and there was no water. They prayed (without ablution) and informed Allah's Apostle about it, so the verse of Tayammum was revealed." Usaid bin Hudair said to `Aisha, "May Allah reward you. By Allah, whenever anything happened which you did not like, Allah brought good for you and for the Muslims in that." Al-Jurf and the time for the `Asr prayer became due while he was at Marbad-An-Na`am (sheepfold), so he (performed Tayammum) and prayed there and then entered Medina when the sun was still high but he did not repeat that prayer.

Narrated Abu Dhar: I said, "O Allah's Apostle! Which mosque was first built on the surface of the earth?" He said, "Al- Masjid-ul-,Haram (in Mecca)." I said, "Which was built next?" He replied "The mosque of Al-Aqsa ( in Jerusalem) ." I said, "What was the period of construction between the two?" He said, "Forty years." He added, "Wherever (you may be, and) the prayer time becomes due, perform the prayer there, for the best thing is to do so (i.e. to offer the prayers in time).