It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Fasting and the Qur'an will intercede for the servant (on the Day of Resurrection). Fasting will say: O my Lord, I kept him away from food and desires during the day, so accept my intercession for him. And the Qur'an will say: I kept him away from sleep at night, so accept my intercession for him. So the intercession of both of them will be accepted." This hadith is sahih (authentic) on the condition of Imam Muslim, but the two Shaykhs (Bukhari and Muslim) did not record it.