There are no means of attaining faith and certainty except through the Qur'an.
Ibn Qayyim Al-JawziyyaWhoever mocks his brother for a sin they repented from will not die till he himself falls into the same sin.
Ibn Qayyim Al-JawziyyaAnd if a person were given all of the world and what is in it, it would not fill his emptiness.
Ibn Qayyim Al-JawziyyaO people who take pleasure in a life that will vanish, falling in love with a fading shadow is sheer stupidity
Ibn Qayyim Al-JawziyyaRepel the thought, for if you don't, it becomes an idea. So repel the idea, for if you don't it will become a desire. So fight against that(desire), for if you don't, it will become a determination and a passion. And if you don't repel that, it will become an action. And if you don't replace it with its opposite, it will become a constant habit. So at that point, it will be difficult for you to change it.
Ibn Qayyim Al-Jawziyya