Silsilat al-Ahadith al-Sahihah

Sayyiduna Sa’d bin Abi Waqqas (may Allah be pleased with him) says: I used to perform the ‘Isha prayer in the Prophet’s Mosque, and after that, I would perform one rak‘ah of Witr. I was asked: Abu Ishaq! You perform only one rak‘ah of Witr (what is the reason)? I replied: Yes, I heard the Messenger of Allah (peace and blessings be upon him) say: “He acts with foresight who performs Witr before sleeping.”