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 Nor do they spend anything that may be spent, small or great, nor do they traverse a valley, but it is written down to their credit, that Allah may reward them with the best of what they have done. 121 ۞ It is not possible for all believers to go out (to fight). So a part of each section (of the population) should go (to fight) in order that the others may acquire understanding of law and divinity, and warn their companions on return so that they may take heed for themselves. 122