"Prayer is that which enables the soul to realize its divinity. Through prayer human beings worship absolute truth, and seek an eternal reward. Prayer is the foundation-stone of religion; and religion is the means by which the soul is purified of all that pollutes it. Prayer is the worship of the first cause of all things, the supreme ruler of all the world, the source of all strength. Prayer is the adoration of the one whose being is necessary."
Ibn Sina, “Kitab al-Najat”