Allah the Exalted says:
“No calamity befalleth save by Allah's leave. And whosoever believeth in Allah, He guideth his heart. And Allah is Knower of all things.” (64:11)
And whoever believes in Allah, He will guide his heart.
And Allah is All-Knowing of everything.
Ibn al-Qayyim, may Allah have mercy on him, said:
Hearts are not granted their desires until they reach their Master.
And they do not reach their Master until they are sound and whole.
This cannot be achieved for them except by opposing their own whims.
For their whims are their sickness, and their cure lies in opposing them.
And Ibn Taymiyyah, may Allah have mercy on him, said:
When faith enters the heart and its sweetness permeates it,
It brings a sense of sweetness, delight, joy, and radiance
That cannot be described to one who has not tasted it.