How can a Muslim be certain that his repentance has been accepted and that God is pleased with him, and how can he remove hypocrisy from his heart and live the joy and sweetness of faith?

The door of repentance is open to every human being, and a believer does not persist in sin; rather, he hastens to repent. He must busy himself with fulfilling the conditions of sincere repentance, renew his faith, and steadfastly obey Allah. As for self-satisfaction and not feeling deficient, this is an illusion that does not afflict one who truly knows Allah. For one who truly knows Allah is never pleased with any of his deeds for his Lord. The Muslim hopes for Allah's mercy and fears His punishment, and does not feel secure from His cunning plan.