it still remains a matter of controversy whether or not the prayer was established as an obligatory  ritual  before imposing the rules of the usual five prayers a day. It is related that obligatory prayer was  established twice a day, in the morning before sunrise and after sunset. It is reported through a chain  of narrators that when the Prophet (Peace be upon him) received the first Revelation, Gabriel - the  angel, proceeded and taught him how to observe Wudu (ablution). When the Prophet (Peace be upon  him) had finished, he took a handful of water and sprinkled it on his loins.
Ibn Hisham reported that when it was time for prayers, the Messenger of Allâh (Peace be upon him)  and his Companions went into a mountain valley to pray secretly. Abu Talib once saw the Messenger  of
Allâh (Peace be upon him) and Ali praying, he asked them what they were up to. When he got to  know that it was obligatory prayer, he told them to stay constant in their practice.
THE QURAISHITES LEARN ABOUT THE CALL:
This stage of the Call, even though conducted in a clandestine manner and on an individual basis, its  news leaked out and assumed a public interest all over Makkah. In the beginning, the Makkan leaders  did not care much about Muhammad (Peace be upon him) and took no heed of his teachings. At first,  they thought that Muhammad (Peace be upon him) was merely a religious philosophist like Omaiyah  bin Abi As-Salt, Quss bin Sa‘idah, ‘Amr bin Nufail and their ilk who used to philosophize on godship  and  religious obligations. But this attitude of indifference soon changed into real apprehension. The  polytheists of Quraish began to watch Muhammad’s movements closely and anxiously for fear of  spreading his Call and producing a change in the prevalent mentality.
For three underground years of activism, a group of believers emerged stamped by a spirit of  fraternity  and cooperation with one definite objective in their mind: propagating and deeply establishing the call  unto Islam. For full three years Muhammad (Peace be upon him) had been content to teach within a  rather narrow circle. The time had, however, come to preach the faith of the Lord openly. The angel
Gabriel had brought him down a further Revelation of Allâh’s Will to confront his people, invalidate  their  falsehood and crush down their idolatrous practices.