الدرر العلمية

If you want your heart to be at ease and your mind to be tranquil, then hold firmly to two things: 1. Strive to remain close to your Lord, the One in whose Hand your affairs lie, and who has nurtured you with His blessings, by performing acts of obedience and staying away from what He has forbidden. 2. Reduce your greed for this worldly life, your attachment to it, and your intense desire for it. For no heart becomes constricted and no worries become overwhelming except through distancing oneself from Allah and becoming attached to the dunya.