Nahj al-Balagha (Peak of Eloquence)

78. A Syrian enquired from Amīr al-mu’minīn: Was our going to fight against the Syrians destined by Allāh? Amīr al-mu’minīn, peace be upon him, gave a detailed reply, a selection from which is hereunder: Woe to you! You take it as a final and unavoidable destiny [1] (according to which we are bound to act). If it were so, there would have been no question of reward or chastisement and there would have been no sense in Allāh’s promises or warnings. (On the other hand) Allāh, the Glorified, has ordered His people to act by free will and has cautioned them and refrained them (from evil). He has placed easy obligations on them and has not put heavy obligations. He gives them much (reward) in return for little (action). He is disobeyed, not because He is overpowered. He is obeyed but not under force. He did not send prophets just for fun. He did not send down the Book for the people without purpose. He did not create the skies, the earth and all that is in between them in vain. That is the imagination of those who disbelieve; then woe to those who disbelieve - because of the fire. (Qur’ān, 38:27)