بِسْم الله الرحمن الرحيم
Firstly, here is Majlisi's commentary on Ibn Junayd's position:
قال المجلسي في الذكرى «وقد خالف ابن الجنيد من الشيعة وذهب على أنها في غير الفاتحة افتتاح وهو متروك. انتهى. وما ورد من تجويز تركها في السورة إما مبني على عدم وجوب السورة كاملة أو محمول على التقية لقول بعض المخالفين بالتفصيل» - بحار الأنوار82/21
Tahreef refers to the physical distortion of the text of the Qur'an, be it deleting verses, modifying them, re-arranging them.
Differing interpretations regarding the same text can never be called tahreef.
You keep insisting to restrict it's form to be only of the physical distortion of the text which is not necessarily always true. And it's not simply just "differing interpretations regarding the same text" that can be used to justify this difference and call an end to it. Disagreeing over the Tanzeel, that is of what constitutes an Ayah will eventually all go down to indirectly claiming that the Tanzeel underwent Tahrif no matter how much you try to brush it all those justifications. Brother, as mentioned in my earlier post, if one was to come and claim that in Surat Al-'Imran; the "Alif Lam Meem", while it is an Ayah in Al-Baqarah, it is not an Ayah in Al-'Imran but part of the text with Bismillah before the Ayah, what would that constitute to? Note that the text in Surat Al-Imran still remains the same in such scenario. Please comment in this.
Brother, the very fact that Ibn Al Junaid rejects that the basmallah is a part of the Qur'an, shows that there is no consensus.
If you like, you can use words like "the majority" or "the correct opinion", but you cannot argue that there is a consensus.
You should also be aware that there are authentic hadiths that are clear proofs that the basmallah is only for the Fatiha and not the rest of the Suwar.
This is narrated by Al Halabi and Misma' Al Basri from Al Sadiq.
It is also natrated by Mohammed bin Muslim from Al Baqir.
They all narrated that the Imam made the basmallah mandatory in Fatiha only, but not other verses.
These narrations are all authentic too.
How can anyone suggest that such strong proofs are invalid because of a so-called "consensus"?
Brother, from what I make out of your assertions here, this is like me arguing that the Sunnis do not hold an Ijma' in the Tahrim of Mut'a merely because one Sahabi('Ibn 'Abbas) opposed the opinion of the majority of the Sahaba in it's Tahrim and instead believed that it was Mubah(from a Sunni perspective). Or that some of the Tabi'in differed on it such as some of the scholars of Mecca where they allowed it. Arguing against the validity of a consensus being made by the contemporary scholars is a separate discussion and will only diverge the current one.
Nevertheless, the fact of the matter is that the agreement which the Imamiyia have came to in affirming that the Bismillah is an Ayah of every Surah was based on the majority of the scholars from the past till now holding that opinion and not considering the minority opinion that rejected it. Hence the Ijma' being established based on the opinion of the majority and not considering the opinion that the minority held that the Bismillah is not an Ayah such as Ibn Junayd. For example, here is what Khui states in his Al-Bayan:
هل البسملة من القرآن ؟
اتفقت الشيعة الامامية على أن البسملة آية من كل سورة بدئت بها ، وذهب إليه ابن عباس ، وابن المبارك ، وأهل مكة كابن كثير ، وأهل الكوفة كعاصم ، والكسائي ، وغيرهما ما سوى حمزة
Khui:
"Is the Bismillah part of the Quran?
The Shi'a Imamiya have come to an agreement that the Bismillah is an Ayah from the beginning of every Surah. And those who followed this opinion were Ibn Abbas, Ibn Al-Mubarak, the people of Mecca such as Ibn Kathir............"(see page 439 and the next few pages) "
http://www.shiaweb.org/quran/bayan/pa78.htmlKhui is speaking on behalf of the Madhab here and affirming that the Imamiyia holds on to one view regarding the Bismillah and does not take into consideration that opinion of Ibn Junayd to be valid. Plus, no one has opposed his view on this, hence the agreement.
^
Maybe it is related to the well-known quote from Majlisi's Mir'at al-'Uqool? [http://en.wikipedia.org/wiki/Shia_view_of_the_Quran#Misconceptions] - interesting that the wikipedia page is trying to dispel false notions attributed to the Shia, yet this matter is quite well known.
Concerning the main topic of the Basmala, I asked one Shaykh, and he basically said that there are different sayings of the Qurra' themselves based on the different indubitable recitations, and the Fuqahaa inclined to a certain opinion based on these differences.
Note that the matter is very different from the Shia sayings, since in the case of us Sunnis, the differences are limited to and based on the mass-transmitted ways of recitation.
Although I didn't want to diverge the discussion to be on the Qira'at and the Ahruf, but since it's related and vital to this issue to some extent, I don't see why not. From an Imami perspective, we do not believe that the opinions of those Qura' who believed that the Bismillah is an Ayah and those that believed that it wasn't an Ayah justifies this difference. For Warsh and Qaloon to say that it's not an Ayah in Al-Fatiha and Hafs saying otherwise is still problematic considering that at the end of the day no matter how you look at it, it all goes back to the fact that the Fatiha has been revealed once like the rest of the Suwar. That is, it's either that Allahس included it as an Ayah in Al-Fatiha or that he didn't include it when He revealed the Sura, but saying that both cases happened is impossible and illogical. Otherwise, if both cases did indeed happen, then there wouldn't be a need for this difference to occur between Abu Hanifa and Ahmed bin Hanbal on this issue where each held to one opinion and not considered the other. They can simply both affirm that Allah revealed the Fatiha twice where he included the Bismillah on the first revelation and didn't include it the second revelation based on the justifications made with the Qira'at. Hence they would acknowledge both opinions to be valid and end this difference.