Imam Ali, the cousin and son-in-law of the Prophet Muhammad PBUH, is a revered figure in Islam and is known for his wisdom and eloquence. Although the following quotes may not all be explicitly about the importance of working hard, they convey the significance of diligence, perseverance, and self-improvement in one's life: "Your remedy is within you, but you do not sense it. Your sickness is from you, but you do not perceive it. You presume you are a small entity, but within you is enfolded the entire Universe." "Strive always to excel in virtue and truth." "The greatest wealth is wisdom; the greatest poverty is stupidity; the worst unsociableness is that of vanity and self-glorification; and the best nobility of descent exhibits itself in politeness and in refinement of manner." "The value of a man depends upon his courage; his veracity depends upon his self-respect, and his chastity depends upon his sense of honor." "He who is aware of his own faults is oblivious to the faults of others." "He who is deserted by friends and relatives will often find help and sympathy from strangers." "Do not feel ashamed if the amount of charity is small because to refuse the needy is an act of greater shame." "People in this world are like travelers whose journey is going on though they are asleep." "If you find that somebody is not grateful for all that you have done for him, then do not get disappointed because often you will find that someone else feels under your obligation though you have done nothing for him." "Endure with patience, and your patience will not be unrewarded." These quotes reflect the wisdom of Imam Ali, emphasizing the importance of self-improvement, perseverance, and the pursuit of knowledge and virtue in one's life.