Being the Word of Allah, the Glorious Qur'an is preserved in the same form it was revealed to Prophet Muhammad (peace and blessings of Allah be upon him) 1400 years ago, and will remain so until the Day of Judgment. This is nothing but the fulfillment of Allah's promise:
"Lo! We, even We, reveal the Reminder, and lo! We verily are its Guardian."
By the same token, no creature has the authority to add to or omit anything from the Glorious Qur'an. This rule applies even to Prophet Muhammad (peace and blessings be upon him) himself. Allah, Most High, says,
"It is a revelation from the Lord of the Worlds. And if he had fabricated against Us some of the sayings, We would certainly have seized him by the right hand, then We would certainly have cut off his aorta, and not one of you could have withheld Us from him. " (Al-Haqqa: 43-47)
As regards your question,
surat At-Tawbah or 'repentance', exposes the true qualities of the hypocrites and threatens them with a woeful doom. It can be likened to a stern warning made in the strongest terms. Hence, an opening which stresses divine mercy and compassion does not seem particularly fitting to the subject matter of the
surah. Therefore, the
surahBismillahi Ar-Rahmani Ar-Rahim", which comes at the beginning of every other
surah in the Qur'an. To recite this phrase at its beginning is forbidden because it constitutes an addition to the Qur'an, which is not part of it.
In his well-known,
The Meaning of the Qur'an,
Sayyed Abu Al-A`la Al-Maududi states: "
Surat At-Tawbah is known by two names: At-Tawbah and Bara'ah. It is called At-Tawbah because it enunciates the nature of
Tawbah (repentance) and mentions the conditions of its acceptance. The second name, Bara'ah (Release), is taken from the first word of the
Surah.
This is the only
Surah of the Qur'an to which the
Basmallah is not prefixed. Though the commentators have given different reasons for this, the correct one that which has been given by Imam Razi is that the Prophet himself did not dictate it at the beginning of the
surah. Therefore, the Companions (may Allah be pleased with them all) did not prefix it and so did their successors. This is a further proof of the fact that utmost care has been taken to keep the Qur'an intact so that it should remain in its complete and original form."