Answer:

1)   The claim for the book “Bayan” which has been sent down for 2 days is merely causeless without any document.

2)   Contrary to the Baha’i proselytizers’ claims it should be said that the heavenly book if the holy Quran has been sent down all together in a night called “Qadr” [power]; in addition to its sending down during 23 years:

"اِنّا اَنْزَلْناهُ فِی لَیْلَهِ الْقَدْرِ"[قدر/1]

“Lo! We revealed it on the night of Power” [Al-Qadr/1]

Consequently, the Islamic narrations are directing on the holy Quran’s sending down all togething in a night.[2]

3)   Studing and investigating the book Bayan, we can figure out that must of its phrases don’t possess new style and order. Even some of its phrases have been written adapted by the holy Quran. So, it could be written better than that less than two days.

4)   Ali Muhammad Shirazi had promised for his book to have 19 units and 19 chapters consisting totally of 361 chapters; however, contrary to his promise, he could write the Persian Bayan in 10 chapters and 9 unites and the Arabic one in 11 units!!! So, he acted against his promise because

"... اِنَّ اللهَ لا یُخْلِفُ الْمیعَادَ" [آل عمران/9]

“Lo! Allah faileth no to keep the tryst.” [Al-Imran/9]