Thank you for sharing this information. This topic perhaps needs a thread of its own and so I won't say too many things here. The Quran has many spiritual truths but that does not mean parts of it is not corrupted. Bahaullah certainly does not seem to suggest that every word in the Quran came from God. The fact that the Caliph Uthman ordered variant copies of Quran be destroyed proves that the Quran has been corrupted. We cannot deny this historical fact. The life of Mohammed has been well documented. If Jews had been turned in to apes by Allah as mentioned in Quran 5:60 and a few other verses, there would be some historical record of it detailing the time, place and the number of Jews who got transformed in to apes. But we have no such record either in Islamic or Jewish or Christian or any other sources. Quite clearly, there is some man-made stuff in the Quran.From a Baha'i perspective there is no doubt as to the authenticity of the quran; These are lengthy quotes, but I post them to show, that as a Baha'i we do not have to doubt, we just have to unravel the secrets enshrined within.
"...the Qur'án was an impregnable stronghold unto the people of Muhammad. In His days, whosoever entered therein, was shielded from the devilish assaults, the menacing darts, the soul-devouring doubts, and blasphemous whisperings of the enemy. Upon him was also bestowed a portion of the everlasting and goodly fruits — the fruits of wisdom, from the divine Tree. To him was given to drink the incorruptible waters of the river of knowledge, and to taste the wine of the mysteries of divine Unity.
"All the things that people required in connection with the Revelation of Muhammad and His laws were to be found revealed and manifest in that Ridván of resplendent glory. That Book constitutes an abiding testimony to its people after Muhammad, inasmuch as its decrees are indisputable, and its promise unfailing. All have been enjoined to follow the precepts of that Book until "the year sixty"1 — the year of the advent of God's wondrous Manifestation. That Book is the Book which unfailingly leadeth the seeker unto the Ridván of the divine Presence, and causeth him that hath forsaken his country and is treading the seeker's path to enter the Tabernacle of everlasting reunion. Its guidance can never err, its testimony no other testimony can excel. All other traditions, all other books and records, are bereft of such distinction, inasmuch as both the traditions and they that have spoken them are confirmed and proven solely by the text of that Book. Moreover, the traditions themselves grievously differ, and their obscurities are manifold.
"Muhammad, Himself, as the end of His mission drew nigh, spoke these words: "Verily, I leave amongst you My twin weighty testimonies: The Book of God and My Family." Although many traditions had been revealed by that Source of Prophethood and Mine of divine Guidance, yet He mentioned only that Book, thereby appointing it as the mightiest instrument and surest testimony for the seekers; a guide for the people until the Day of Resurrection."
(Bahá'u'lláh, Kitáb-i-Íqán, pars. 220-222)
"Consider, how He hath appointed and decreed this self-same Book, the Qur'án, as a guidance unto all that are in heaven and on earth. He, the divine Being, and unknowable Essence, hath, Himself, testified that this Book is, beyond all doubt and uncertainty, the guide of all mankind until the Day of Resurrection. And now, We ask, is it fair for this people to view with doubt and misgiving this most weighty Testimony, the divine origin of which God hath proclaimed, and pronounced it to be the embodiment of truth? Is it fair for them to turn away from the thing which He hath appointed as the supreme Instrument of guidance for attainment unto the loftiest summits of knowledge, and to seek aught else but that Book? How can they allow men's absurd and foolish sayings to sow the seeds of distrust in their minds? How can they any longer idly contend that a certain person hath spoken this or that way, or that a certain thing did not come to pass? Had there been anything conceivable besides the Book of God which could prove a more potent instrument and a surer guide to mankind, would He have failed to reveal it in that verse?
"It is incumbent upon us not to depart from God's irresistible injunction and fixed decree, as revealed in the above-mentioned verse. We should acknowledge the holy and wondrous Scriptures, for failing to do this we have failed to acknowledge the truth of this blessed verse. For it is evident that whoso hath failed to acknowledge the truth of the Qur'án hath in reality failed to acknowledge the truth of the preceding Scriptures. This is but the manifest implication of the verse. Were We to expound its inner meanings and unfold its hidden mysteries, eternity would never suffice to exhaust their import, nor would the universe be capable of hearing them! God verily testifieth to the truth of Our saying!"
(Bahá'u'lláh, Kitáb-i-Íqán, pars. 224-225)
"...the unfailing testimony of God to both the East and the West is none other than the Qur'án. Were it beyond the comprehension of men, how could it have been declared as a universal testimony unto all people?"
(Bahá'u'lláh, Kitáb-i-Íqán, par. 232)