Islam Critiqued is no book thief; Dhul Qarnayn was borrowed?

In answer to the video "Abraham and the Kaaba: From Borrowed Stories to Sacred Scripture"

The Alexander Romances, although often believed by critics of Islam as being the source of the Quranic Dhul Qarnayn, has an unclear date of composition, spanning between the 4th and 16th centuries. That is why it is legitimate to speculate that the borrowing charge against the Quran has less ground to stand on than the reverse, with the various authors of the romances actually inspiring themselves throughout time by the Quran and its comentaries.

The Alexander Romances is thought to be based on the lost Greek writing called Pseudo Callisthenes whose closest copy is a 5th century Armenian translation. What is of concern to Islam critics are the shallow and far fetched similarities between the Quran and the Syriac translation, of which no manuscript exists prior to the 18th century, and in which by the way Alexander is never given the title "two horned".

As to the 14th-16th century Ethiopic translation in which he is called "two horned", besides being irrelevant in trying to establish the title by which Alexander was known around the time of the revelation of the sura in 620, it is important noting that this work contains the authors' interpretative opinion and is based on earlier Arabic translations.

But back to the Syriac translation which is of main interest to the accusers.

Although originally believed to have been finalized towards the mid 7th century CE, this Syriac legend of Alexander ends with a passage about the gates built by Alexander and stresses parallels between him and Heraclius, the Byzantine Emperor. More importantly this same passage retrospectively "prophecizes" the invasion of the Huns in 515 CE and the coming of Heraclius in 629 CE, leading scholars to assume the passage is a later addition, written as a Byzantine propaganda shortly before the Muslim conquest of Syria around 634CE. It additionally speaks of an independent and major Arab Kingdom which can only be equated with the early Caliphate. In that conquest the Persians are contrasted with the Sassanids, and the Greeks with the Romans. This pushes the finalization of the passage to post date the revelation of sura Kahf pre-620CE. (as a side note even if one would be to assume the sura is Medinan then the onus is on him to prove it post dates the finalization of the Syriac romance).

Similarily and towards the late 7th century, a Syriac Christian adaption of the Alexander romance, called the Apocalypse of Pseudo-Methodius, was written as a response to the Muslim invasions equating Gog and Magog with the Muslims. Other factors have led scholars to push the final composition of the passage further to between the 8th and 15th century, as it was clearly reshaped as a means by which the author sought to console, through parallelisms, the Christians who had lost Constantinople to the Ottomans.

In short besides the Armenian translation which was itself reedited in the 13th century, all other versions have their earliest manuscripts post dating the Quran by centuries. This means that all these texts were written in an Islamic environment, including the Armenian translation, which could have affected the later development of the Alexander Romances.

Now although late manuscripts themselves arent problematic, they become so when one attempts establishing a borrowing claim from text to text. Besides the proven additions, it is impossible to determine what the Syriac text looked like towards its earliest potential time of inception, in 629CE. Even if one takes this earliest estimate, it still leaves the Syriac author with long enough time to be exposed to the Quranic Dhul Qarnayn, again revealed pre-620, orally or textually, integrating the Quranic elements so as to fit and embelish the Christian agenda as was done a few decades later in Pseudo-Methodius.

Even Josephus and Jerome's respective works with short passages alluding to a wall built by Alexander are known evolving texts and their earliest manuscripts post date the Quran by hundreds of years, and were both finalized when Pseudo-Methodius had gained sweeping influence accross europe. Finally, there exists zero proof that the similarities between the romances and Dhul Qarnayn were in oral circulation all over the middle East and Europe prior to the revelation of sura kahf circa 620CE while plenty evidence exists pointing to the finalization of all available versions of the romances, more particularily the passages with Quranic similarities, after the revelation of the sura and the spread of Islam.

Even if for argument's sake these traditions were in circulation, then it would still do nothing to undermine the Quran's authenticity. All these sources draw on earlier lost sources, as shown earlier, with the life stories of Cyrus the Great being the main inspiration. This puts these shallow critics in a lonely corner yet again, similarity between any of those alleged Quranic sources does not prove plagiarism. The common denominator between all of these sources, including the Quran, is the truth.
Now the manner in which that common truth found its way in the Quran is a matter of faith. To Muslims, it is divine revelation, and the opponents have nothing to disprove it.

There are many other Quranic stories besides that of Dhul Qarnayn, which are true and that are found in previous traditions. The same is the case with the Biblical text. The Quran doesnt shy away from that reality and in fact embraces it, being the muhaymin/guardian of the truth that is still found scattered among previous scriptures and traditions.