Verily Allah does not waste the reward of the good-doers.
“And neither do they expend anything (in the way of Holy Struggle), small or great, nor do they cross any land, but it is recorded for them,*** so that Allah may reward them with better than what they used to do.” There is no expense, whether it be small or large, that the Muslims spend in charity, nor do they cross any desert, but it is recorded for them, in order that Allah will recompense them with something better than that which they have done.
The verse says: “And neither do they expend anything (in the way of Holy Struggle), small or great, nor do they cross any land, but it is recorded for them, so that Allah may reward them with better than what they used to do.” When we refer to the history of the Battles of the advent of Islam, we realize that the Muslims were confronted with a great deal of hardships and difficulties in many of those Battles.
They suffered much pain because of scarcity of possibilities, martial means and equipments, provisions, and ammunitions. They had to tolerate both thirst and hunger. Whatever they had they spent in the way of Allah. They were surrounded by some insupportable problems. They became wounded, they were slain, but they bore all of these hardships in order to protect the life of the Prophet (S) and to cause Islam victorious.
“And it is not for the believers to go out (to fight) totally; why should not then a group from every*** party of them go forth to become learned in religion, and to warn their people when they return to them. So that they may beware?” In the previous verses, the Muslims were emphatically called toward Holy Struggle, and those who offended that commandment were severely criticized. Now, this verse attracts the attention of the Muslims toward another important duty that they have.