O People who Believe! Fear Allah, and be with the truthful. 119 It was not [proper] for the people of Madinah and those surrounding them of the bedouins that they remain behind after [the departure of] the Messenger of Allah or that they prefer themselves over his self. That is because they are not afflicted by thirst or fatigue or hunger in the cause of Allah, nor do they tread on any ground that enrages the disbelievers, nor do they inflict upon an enemy any infliction but that is registered for them as a righteous deed. Indeed, Allah does not allow to be lost the reward of the doers of good. 120 Also, they would not have spent anything, great or small, for the cause of God or travel through a valley without God decreeing a reward for them far better than whatever they had done. 121 ۞ With all this, it is not desirable that all of the believers take the field [in time of war]. From within every group in their midst, some shall refrain from going forth to war, and shall devote themselves [instead] to acquiring a deeper knowledge of the Faith and [thus be able to] teach their home-coming brethren, so that these [too] might guard themselves against evil. 122