“Hearts have times of eagerness and turning towards, and times of weariness and turning away. So make the most of them when they are eager, and leave them be when they are weary.”

Scholars have read this as advice about voluntary worship: the obligations stay fixed whatever the heart feels, but the extra reading, prayer and remembrance should be pressed when the heart is keen and eased when it is tired, so that it does not come to resent them. Abu Nu‘aym records it with its chain in Hilyat al-Awliya’.