Explanation: In the Chapter on Certainty and Reliance upon Allah, the author next cites the hadith of al-Barāʾ ibn ʿĀzib (may Allah be pleased with him). The Prophet (blessings and peace be upon him) instructed him that, when he retires to bed, he should recite this supplication—a formula that expresses consigning one’s affairs to one’s Lord, relying upon Allah both outwardly and inwardly, and entrusting everything to Him.

The Prophet also told him to lie on his right side, for that is superior. Physicians have observed that sleeping on the right side is better and healthier for the body than sleeping on the left. Some spiritual teachers add that it helps a person wake up more readily: sleeping on the left side causes the heart to rest and delays wakefulness, whereas sleeping on the right keeps the heart alert, makes one’s sleep lighter, and thus allows one to awaken quickly.

Another point in the hadith is that the Prophet (peace be upon him) ordered him to make these words the last thing he said before sleep, even though other forms of remembrance are also prescribed at bedtime—for example, saying subḥān Allāh thirty-three times, al-ḥamdu lillāh thirty-three times, and Allāhu akbar thirty-four times. Nevertheless, the hadith of al-Barāʾ (may Allah be pleased with him) shows that the supplication the Messenger of Allah taught him should be the final words he utters.

Al-Barāʾ ibn ʿĀzib (may Allah be pleased with him) then repeated the supplication back to the Prophet to ensure he had memorized it accurately, saying: “I believe in the Book You have revealed and the Messenger You have sent …”