Wahb ibn al-Ward, when asked about the reward of a particular deed, said,

“Ask not about its reward, but ask about the gratitude due upon the one who was guided to it.”

(Abu Nu’aym, vol. 8, p. 155.)

(Read on pg 34, Ibn Rajab al-Hanbali, The Journey to Allah. Daar us-Sunnah Publishers. Birmingham: 2007.)