As you are aware, each Surah has its specific name. For instance Surahs: Al-Fatiha, Al-Baqara, Al-Imran, An-Nisa and so on. I was wondering if Allah named these Surahs with current names? Or the Prophet (pbuh) chose their names?
Or even Imam or Kholafa named them?
Initially the surahs were demarcated but not named the way we see today. They were identified by some peculiarity mentioned in them. For example, to refer to Surah Al-Baqarah the phrase "the surah in which cow is mentioned" was spoken. With the passage of time it was shortened.
Narrated by Al-Amash: I heard Al-Hajjaj saying on the pulpit, "The Sura in which Al-Baqara (the cow) is mentioned and the Sura in which the family of 'Imran is mentioned and the Sura in which the women (An-Nisa) is mentioned." (Bukhari Volume 2, Book 26, Number 806)
Similarly it has been narrated in Musnad Ahmad ibn Hanbal:
Uthman ibn Affan said: ...and when some verses used to reveal to him, he (the Prophet) would say "place these verses in the surah in which so and so is mentioned..." (Musnad of Uthman ibn Affan, Number 499)
This shows that the surahs were named neither by God nor by the Prophet. Their peculiarities which the Prophet mentioned while referring to them were shortened to form their names.
PS> I could not locate an online version of Musnad
