If a man's patience is stronger than his whims and desires, then he is like an angel, but if his whims and desires are stronger than his patience, then he is like a devil. If his desire for food, drink and sex is stronger than his patience, then he is no better than an animal.

Wasting time is worse than death, because death separates you from this world whereas wasting time separates you from Allah

The ibtilaa' (testing) of the believer is like medicine for him. It cures him from illness. Had the illness remained it would destroy him or diminish his reward and level (in the hereafter). The tests and the trials extract these illnesses from him and prepare him for the perfect reward and the highest of degrees (in the life to come).

The perfection of Tawheed is found when there remains nothing in the heart except Allaah

How is it possible for one’s heart to be certain that one is going to meet Allah, that Allah sees and hears all that he does, and knows his secret open affairs, and that he will be made to stand before Allah, answerable for all his deeds - how can one be certain and aware of all of this, and yet persist upon things which displease Allah; persist upon abandoning Allah’s orders, neglecting His rights, and yet claim that he has good expectation of Allah?

Every gulp of air that goes out in a cause other than the cause of Allah will turn to sorrow and regret on the Day of Judgement.

When there is money in your hand and not in your heart, it will not harm you even if it is a lot; and when it is in your heart, it will harm you even if there is none in your hands.