Asalamu Alaikum Warina
Hope you are doing well. May Allah Almighty reward you for sending your question. Indeed, it is always good to hear from our brothers and sisters and be able to provide them with information that can help them better understand their religion.
Muslims believe that the divinity of the Quran and its authenticity is an issue beyond any doubt, as it has been proven through many textual and intellectual evidences, something that no other book can claim.
This is not only because it is a miraculous book, but also because it was revealed as the final and everlasting source of guidance for all humankind till the day of Judgment.
Every letter and word in the Quran has been handed down to us through generations and centuries in the absolute same form in which it was revealed.
Yet, the question you raised regarding the names of the surahs (chapters) of the Quran is valid: Were the surahs given their names during the time of the Prophet (PBUH), or were they given their names later on?
The majority of Muslim scholars agree that the names of the surahs were based on revelation. This means that it is either that Almighty Allah sent Gabriel down with the names of the surahs to the Prophet (PBUH), who told the Companions about them. Or the Prophet himself was guided to name them, and then revelation came in support of the name chosen.
The first of these two opinions is adopted by the majority of Muslim scholars, who are specialized in the sciences of the Quran. As Jalal al-Din Al-Suyuti says:
It has been proven that the names of the surahs have all been given by means of tawqeef (Divine guidance through revelation). (Jalal al-Deen Al-Suyuti, Al-Itqan fi Ulum Al-Quran, vol. 1, Cairo, n.d., p. 147)
This is even proven by many hadiths (Prophetic traditions) that mention the names of the surahs as we know them today. For instance, An-Nawwas ibn Sam`an narrated that he heard the Messenger of Allah (PBUH) saying:
On the day of Judgment, the Quran and its people who used to stick to its teachings will be brought with (the chapters) Surat Al-Baqarah and Aal `Imran preceding them. (Muslim)
Abdul-Rahman ibn Yazid also narrated that he heard Ibn Masud (may Allah be pleased with him) saying:
Banu Isra’eel (i.e. Surat Al-Israa’), Al-Kahf, Maryam, Taha, and Al-Anbiyaa’ are among the early surahs that I have learned by heart. (Al-Bukhari)
This shows that the surahs of the Quran were known by the same name during the lifetime of the Prophet (PBUH), and it was the Prophet who gave them the names based on revelation he received from Almighty Allah, as is the opinion of the majority of Muslim scholars.
Yet, there is one important point to be highlighted here. Why do we hear many names of some surahs? For instance, Surat Ash-Sharh is also called Al-Inshirah and Alam Nashrah. Why is that?
We have to differentiate here, between what is written in the mushaf (copy of the Quran) as the name of the surah, and what is being used by people to refer to a surah, which could be the first words of the surah or another derivative of its name.
This obviously does not contradict the fact that the Quran is preserved and protected because the name of the surah is the same in the mushaf, and no one can change that.
The other point is that there are some surahs that were given more than one name by the Prophet (PBUH). Although we can use any of these names, we still prefer to use what is mentioned in the mushaf, as this is the most common name used among people.
For example, we quote the fact that Surat Al-Israa’ was also called Bani Israel by the Prophet (PBUH), Surat Al-Fatihah was called Umm Al-Quran and As-Sab` Al-Mathani, and so on.
These other names of the surahs can be known by looking into specialized books. Yet, the fact remains that these names were revealed to the Prophet (PBUH) and one of them was frequently chosen by him to refer to the surah.
Part of the accuracy of Muslims is that they narrated the other names and they can still be alternatively used to refer to the surah. But the recommendation is that we use the surah titles that are in the mushaf, as they are the most commonly used.
In all cases, the names mentioned in the mushaf have been the same, none of them have been subjected to any change. The simple reason for this is the fact that the Quran is a protected book.
Part of Muslims’ faithfulness in protecting the Quran is to mention anything relevant to it with accuracy and exactness, and this is what has been done with the names of the surahs.
I hope this answers your question. Please keep in touch.
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