No one can indulge in unlawfulness except for two reasons, the first thing which is failing to trust Allaah, despite the fact that if one obeys Him, he will surely be granted the best of lawful gains. The second reason is knowing that whoever abandons anything for the sake of Allaah, surely He will grant him something better than what he has abandoned. Unfortunately, his vain desires surpass his patience and his inclination overpowers his mind. The first one has poor knowledge, and the second one has poor insight.
Yayha bin Mu’adh said, “He whom Allaah opens his heart with invocation, surely Allaah will respond to him. “I added, “but he whom Allaah opens his heart, and feels in need of Allaah and his hope is strong, then Allaah will respond to him”