Challenge of the tribes. When Abu Bakr rejected the demand of the tribes to exempt them from the payment of the Zakat, they had no argument to meet the argument of Abu Bakr, but in a state of desperateness they took such refusal as a challenge. Islam sat lightly on them, and tribal feelings were most dominant in them. They accordingly decided that if Islam involved the payment of Zakat to Madina, they would prefer to forego Islam, rather than yield to the dictates of the authorities in Madina. During their stay in Madina the delegates of the tribes saw for themselves that with the departure of the main Muslim army under Usamah for Syria, there was hardly any fighting force with the Muslims in Madina and as such the city was vulnerable. When the delegates returned to their tribes and gave an account of what Abu Bakr had said feelings ran high among the tribesmen. They decided to attack Madina when the main Muslim army was away, and teach the authorities of Madina a lesson. The tribes concentrated their forces at Zul Hissa and Zul Qissa to the north east of Madina on the way to Nejd, and decided to launch the attack against Madina.

Preparations of Abu Bakr. When the delegates of the tribes left Madina in a sullen mood, Abu Bakr discerned that they meant mischief, and that an attack by the tribes was imminent. Abu Bakr lost no time in making arrangements for the defense of Madina. Strong pickets under Khalid, Zubair, Talha, Abdur Rahman b Auf, Abdullah b Masud and Ali were posted at strategic approaches to the city. These pickets were required to remain at their posts, and to make immediate report to the Caliph about the movements of the tribes. All the adult male Muslims were asked to collect in the Prophet's mosque. Here Abu Bakr apprised them of the impending danger of an attack from the tribes, and asked them to do their duty to Islam. Abu Bakr brought home to them the point that if they staked their everything in the way of God, God would come to their help as He had helped them during the life time of the Holy Prophet. A roster of all Muslim male adults in the city was prepared, and their turns for keeping the vigil during the nights were fixed.

The attack of the tribes. One dark night during the month of July 632 C E. there was brisk movement in the camp of the tribes at Zul Hissa. The Muslim scouts brought the intelligence that the tribes planned to attack Madina that night. Abu Bakr collected all the Muslim male adults in the mosque. After the night prayers these men were required to spread out in groups to keep vigil in the various quarters of the city. At the head of a contingent Abu Bakr took position at a strategic point in the direction of Zul Hissa from where the attack was expected. The tribes launched the attack at midnight. They had hoped that they would take the city by surprise, and that as there was no fighting force in Madina, they would meet no resistance, and it would be an easy walk-over for them. As the tribal force advanced in the darkness of the night fully assured of their victory, the contingent of Abu Bakr leapt on the advancing horde, and took them by surprise. Many tribesmen fell victims to the swords of the Muslims; the rest fled in utter confusion.

The counter attack of the Muslims. The Muslims gave chase to the enemy and advanced to Zul Hissa. Here the retreating tribesmen were joined by their reserves. In the battle at Zul Hissa the Muslims were outnumbered but they fought with grim determination. As a stratagem the tribesmen threw inflated water skins in the path of the Muslim army. That frightened the camels on which the Muslims were riding, and the camels did not rest till they reached Madina. The tribes felt jubilant at what they regarded as the repulse of the Muslims. The tribes thinking that all was over with the Muslims retired to their camps at Zul Hissa and Zul Qissa.