In Choosing Between Voluntary Acts of Worship
Imām Ibn Taimiyyah, may Allāh have mercy on him, said:
An act of worship that [a slave of Allāh] gets benefits from—his heart attentive in it, desiring it, and loving it—is better than an act of worship he performs inattentively and without desire, like nourishment a person craves when he’s hungry: it’s of greater benefit to him than nourishment that he has no desire for, or [one] he eats when he’s not hungry.
Majmūʿ Al-Fatāwá, vol. 22, p. 348.