Thus, performing a good deed has praiseworthy effects that are present (1) within the soul and outwardly. Performing (2) bad deeds likewise has its effects. Allah Most High has made good deeds the cause of the former, [and bad deeds the cause of the latter, just as He has made consuming poison a cause of illness and death. The causes of evil also have counteracting causes by whose operation they are repelled] (3). Thus, sins are effaced through repentance and righteous deeds, and the calamities of this world expiate sins. Similarly, the necessary effect of poison is sometimes counteracted with medicine, while at other times it causes a minor illness followed by recovery.

If it is said, “Creating the act while punishment results from it (4) is injustice,” this is tantamount to saying, “Creating the consumption (5) of poison and then allowing death to result from it is injustice.” Injustice is placing something where it does not belong. The doer’s deserving the consequence of his act—which is disobedience to Allah—is like his deserving its consequence when he wrongs people (6).

This now leads (7) to the question of judging acts to be good or evil. All people agree that reason may discern whether an act causes a person benefit and brings about what accords with him, or causes him harm and brings about what is contrary to him. Reason may likewise discern whether an act constitutes a quality of perfection or deficiency. They differ only over whether it [is] (8) a cause of punishment and censure, according to two well-known positions.