The Banu Amir ibn Auf to whom the hamlet of Quba belonged, now arrived, transported with joy, to invite to sojourn in their midst the illustrious guest sent to them by Allah. The Prophet lodged with Kulsum ibn Hidmi; Abu Bakr with Khubib ibn Saf, while the other Muhajirun took up their quarters with Sad ibn Khazimah, one of the Najibs. [Sidenote: THE ERA OF THE HEGIRA] This happy ending of Mohammad's journey took place on a Monday, at noon, the twelfth day of the month Rabi'u'l-Awwal. The year of this emigration, renowned under the name of "Hijrah" (called "Hegira" by the Europeans), has been adopted by Mussulmans for the beginning of their era. It corresponds to A.D. 622. At first, such a choice creates surprise, and yet no other event in the Prophet's existence exercised more decisive influence over the world-wide success of his cause. Had he remained in Makkah, granting even his final triumph, Islam would have remained there with him. The Arabs of all Arabia, fearing the power with which Islam endowed the Quraish alone, would have formed a coalition to prevent it spreading out of the Sacred City. Whereas, after having begun, despite all malice, to plant the roots of his religion firmly in his native town, it was easy for the Prophet to return there when he had won over the rest of the Arabs to his cause. This proves how impenetrable are the designs of Providence, and how frequently the misfortunes with which God afflicts us, burdening us with suffering, determine the cause of our successes. If the Prophet had not been persecuted and banished by his own people, he would never have been able to fulfil his universal mission, and the world would never have been enlightened by Islam. The Prophet sojourned at Quba Tuesday, Wednesday and Thursday. All rejoined him there. His faithful henchman, after having restituted all the deposits confided to his care to their rightful owners, arrived at Quba, his feet badly lacerated, having tramped night and day. Mohammad embraced him warmly, bandaged his wounds with his blessed hands, and made him rest by his side in Kulsum's dwelling. Mohammad also busied himself with laying the first brick of a Mosque--the first place of public prayer in Islam--and left to Ammar ibn Yasar the care of finishing it. This Mosque was called "At Taqwa," _i.e._ the Mosque of "The Fear of God." Reference is made to it in these verses: "_There is indeed a Mosque founded from its first day upon the fear of God; More right is it that thou take thy stand therein; therein are men who aspire to keep themselves pure and Allah loveth those who purify themselves._" (THE QUR'AN, IX, 109.) [Sidenote: ARRIVAL OF THE PROPHET AT YASRIB]