Some scholars said that one salām suffices in a voluntary prayer but not in an obligatory prayer, (1) because it is reported from the Prophet, peace and blessings be upon him, “that he gave one salām in the witr prayer, facing straight ahead.” (2) They said: Voluntary prayers may allow concessions that are not allowed in obligatory prayers.
These, then, are three opinions. The prudent course is to make two salāms, for if you make two salāms, no scholar will say that your prayer is invalid; whereas, if you make only one salām, some scholars will say that your prayer is invalid. It is well known that the Prophet, peace and blessings be upon him, instructed caution where the evidence is not clear. He said: “What is lawful is clear, and what is unlawful is clear, and between them are doubtful matters. Whoever avoids the doubtful matters has safeguarded his religion and his honour, while whoever falls into doubtful matters falls into what is unlawful.” (3)
He also said: “Leave what makes you doubt for what does not make you doubt.” (4) If you make the second salām, you have performed a remembrance by which you draw near
(1) Al-Mughni, 2:244.
(2) Narrated by al-Tirmidhi, Book of Prayer, chapter: Regarding the Taslim in Prayer, no. 296; Ibn Majah, Book of Establishing the Prayer, chapter: One Who Gives a Single Taslim, no. 919; Ibn Khuzaymah, no. 729, who authenticated it; and al-Hakim, 1:230, who authenticated it according to the criteria of the two Shaykhs, and al-Dhahabi agreed with him.
Imam Ahmad also narrated from Aishah, may Allah be pleased with her, with the wording: “Then he would sit, recite the tashahhud, and supplicate; then he would give a single taslim, saying, ‘Peace be upon you,’ raising his voice with it until he woke us,” 6:236. Al-Albani, may Allah have mercy on him, authenticated it in Al-Irwa, 2:32.
(3) Narrated by al-Bukhari, Book of Faith, chapter: The Virtue of One Who Safeguards His Religion, no. 52; and Muslim, Book of Transactions Involving Irrigation and Agriculture, chapter: Taking What Is Lawful and Leaving Doubtful Matters, no. 1599 (107).
(4) Narrated by Imam Ahmad, 1:200; al-Tirmidhi, Book of the Description of the Day of Resurrection, no. 2518, who said: “A sound, authentic hadith”; and al-Hakim, 2:13, who authenticated it.