Imām Ibn al-Qayyim (d. 751 AH) said:

A servant of Allāh does not partake in that which has been made ḥarām for him except in relation to one of two reasons:

1. Holding a negative outlook with regards to His Lord. In a state of certainty that, if he was to obey him and prioritise His obedience over all else, He would still not grant him that which is ḥalāl and better than that which he has partaken in from ḥarām.
2. He is certain that He will grant him better than it. For, indeed, the one who leaves something for Allāh is recompensed with that which is better than what he has left. However, he partakes in the ḥarām as his lust has overcome his patience; his misguided desires have outwitted his own intellect.

The first represents a weakness in knowledge. While the second represents a weakness in foresight and intelligence.

Yahyá ibn Muʿādh said:

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Whomever Allāh allows to gather his heart upon invoking Him will never have his invocation rejected.

I [Ibn al-Qayyim] say: ‘Gather his heart’ that is, his need and destitution is true and honest before Him, bolstering the hope he possesses upon invoking Him. Such an invocation almost never goes unanswered.

Source: Al-Fawāʾid: 63
Translated by: Riyāḍ al-Kanadī