Al-Imam Ali (p.b.u.h), said:

Hadith n. 77
It is related that when Dirar ibn Hamzah (the correct: Damrah) ad-Dibabi (or as-Suda’i) went to Mu’awiyah, and Mu’awiyah enquired from him about Amir al-mu’minin, peace be upon him, he said: I stand witness that I have seen him on several occasions when night had spread and he was standing in the niche (of the mosque) holding his head, groaning like a man bitten by a snake and weeping as a grieved man, saying:

O world, O world! Get away from me. Why do you present yourself to me? Or are you eager for me? You may not get that opportunity to impress me. Deceive some other person. I have no concern with you. I have divorced you thrice whereafter there is no restitution. Your life is short, your importance is little and your aspirations are base. Alas! The provision is little, the way is long, the journey is far and the goal is hard to reach.

Hadith n. 78: On Predestination
A Syrian enquired from Amir al-mu’minin: Was our going to fight against the Syrians destined by Allah? Amir al-mu’minin, 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 (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 Allah’s promises or warnings. (On the other hand) Allah, the Glorified, has ordered 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’an, 38:27)

Source: https://www.al-islam.org/nahjul-balagha-part-2-letters-and-sayings