If one attains (what he desires), he is pleased and if he is unable to attain it, he becomes discontented.  Such a person is a slave [‘abd] to the things he desires.  He is a slave of it, since true slavery and servitude are the enslavement and servitude of the heart.

—Ibn Taymiyyah [d. 728H/1328CE]

[Ibn Taymiyyah’s Essay on Worship, pp. 100-101]

(Read on pg 50. Dr. Abu Ameenah Bilal Philips, A Commentary on Ibn Taymiyyah’s Essay on the Heart. Dalwah Corner Bookstore. Kuala Lampur: 2008.)