O you who believe! be careful of (your duty to) Allah and be with the true ones. 119 It was not worthy of the people of Madina, and the Arabs of the desert around them, to abandon the Prophet of God, and to care more for themselves than for him; for there is no hardship or thirst or hunger that they know in the service of God, and no place they walk on where walking provokes the unbelievers, and no harm they receive from the enemy, but is put down as a good deed in their favour. Surely God does not let the recompense of those who do good to go waste. 120 And they expend not an expending, small or great, or transverse a vale, but it is written down unto them, so that Allah may recompense them with the best for that which they have been working. 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