Allamah Hilli...

Allamah Hilli, a great Shi’a scholar, in his comments on Al-Yāqút by al-Nawbakhti writes: The principle, on which the problems concerning justice depend is that God is the Wise, He never does an evil action and He never fails to perform any necessary ( wājib ) action. When this principle is proved questions concerning justice, such as goodness of obligation ( taklif ), necessity of Grace ( lutf ) and the like are constructed upon.

And since this principle depends on knowing good and evil and their rationality, the author started his discussion with these.13 Else where he writes: Imamites and their followers, the Mu 'tazilites, believe that goodness and badness of some actions are known by reason evidently such as our knowledge of goodness of beneficial telling truth and badness of harmful lies, on which no reasonable person have doubt, and his certainty about this is not weaker than his certainty about the need of a contingent being [in its existence] to a cause or about the equality of two things which are each equal to a third thing.

They believe that there are some actions, understanding of whose goodness or badness needs reflection such as goodness of harmful telling truth and badness of beneficial lies, and finally that there are some actions, on which reason is unable to make judgement and their goodness and badness is to be expressed by the religious law, Shar', such as [how to perform] worships.14 On the other hand, there are the Ash'arites who deny rationality of goodness and badness.

Shahrestani in his Al-Milal wa al-Nihal describes the idea of Ash'arites as follows: All obligations are to be learnt from the scriptures. Reason (al-'aql) does not make any thing obligatory and does not make anything deserve to be considered as good or bad. Thus, knowing God becomes possible by reason and becomes obligatory (wājib) by the scripture (sam'). God, the most High, says: “We have never chastised unless we have despatched some messenger”.

(The Qur'an, 17:15) Similarly, gratitude to the blessing-giver, rewarding the obedient and punishing the disobedient all become obligatory ( wājib ) by the revealed, and not reason. ( Vol. 1, p. 115 ) In contrast, the Shi’a and the Mu 'tazilites have argued that if goodness and badness were just religious and not understandable by reason, unbelievers would not recognise them today or before they knew of revelations e.g. the Qur'an.