“If one attains (what he desires), he
is pleased & 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 & servitude are the enslavement & servitude
of the heart.”
-Ibn
Taymiyyah [d. 728H/1328CE]
[Ibn
Taymiyyah's Essay on Worship, pp. 100-101]