As report after report came in of fresh defection, Abu Bekr could but instruct his officers to hold on where they were able with the loyal few, hoping to tide over the crisis till the return of Osâma’s force. For the immediate defence of Medîna he took such measures as were possible. He called in all that remained of the faithful tribes in the neighbourhood, and posted pickets at the various approaches to the city. The turbulent tribes in the near desert to the east were the first to assume a threatening attitude. The Beni Abs and Dzobiân massed there in such numbers ‘that the land was straitened by them,’ and they parted into two bodies, one at Rabadza,[17] the other at Dzul Cassa, the first station from Medîna on the road to Nejd. The false prophet Toleiha sent his brother with men to help them; but they still vacillated between the claims of the pretender and Islam. At last they bethought themselves of a compromise. They sent a deputation to Abu Bekr, offering to hold by Islam and its ritual if only they were excused the tithe. The strangers bearing the message were welcomed by the chiefs of Medîna, but by the Caliph their advances were indignantly rejected. He would relax not a tittle of the legal dues. ‘If ye withhold but the tether of a tithed camel,’ said Abu Bekr, bluntly, ‘I will fight with you for the same.’ With this refusal they retired, and also with the intelligence that the city had but few defenders left. Now was the time, before the army came back, not only for plunder, but to deliver a decisive blow. Abu Bekr, foreseeing this, redoubled his precautions. He strengthened the pickets, and set over them the chief men who had remained with him--Aly, Zobeir, Talha, and Abdallah ibn Masûd. For the rest of the people he appointed the Great Mosque a rendezvous. ‘The land hath rebelled against us,’ he said, ‘and they have spied out our nakedness and the weakness of our defence. Ye know not whether they will come upon you by night or come upon you by day, or which of you may be first attacked. They verily hoped that we should have accepted their offer, but we rejected it. Wherefore be vigilant and ready.’ [Sidenote: Attack on Medîna repelled.]