from ruwaym al-baghdadi, a companion of al-junayd:
al-shukr istifragh al-ṭāqah
my rough translation:
gratitude: exhausting the capacity
in other words:
gratitude means spending all you’ve got for Allah
terjemahan kasar:
syukur ialah membelanjakan segalanya kerana Allah.
ref:
al-risalat al-qushayriyya, bab al-shukr