The sinner does not feel any remorse over his sins, that is because his heart is already dead

The heart, in its journey to Allah, Majestic is He, is like that of a bird; Love is its head, and fear and hope are its two wings. When the head and two wings are sound, the bird flies gracefully; if the head is severed, the bird dies; if the bird loses one of its wings, it then becomes a target for every hunter or predator.

Patience is that the heart does not feel anger towards that which is destined and that the mouth does not complain.

Happiness is attained by three things: being patient when tested, being thankful when receiving a blessing, and being repentant upon sinning.

And verily for everything that a slave loses there is a substitute, but the one who loses Allah will never find anything to replace Him.

And to have spent the night sleeping and awoken regretful, is better than to have spent the night standing (in prayer) and awaken impressed with oneself!

The sea of pleasures may drown its owner and the swimmer fears to open his eyes under the water.