The fact that the Uthmanic mushafs differed is known by two ways:
Code:
1) The Qira'at (ie. recitiations that are derived from the Ahruf): Between the various qira'at, there occured changes in letters and sometimes words that cannot be attributed to one script, even if this script were without dots and vowel marks. For example, some of the Qira'at [304] read 91:15 as 'wa laa yakhaafu..." This is the recitation that most of the readers will be familiar with. On the other hand, other Qiraa'at [305] read it as 'fa laa yakhaafu...', changin the waw to a fa. This letter change can not be attributed to the same script, and must indicate a difference in the Mushafs of Uthman. [306] Another example is the qiraa'a of Ibn 'Aamir, who read 3:184 as 'wa bi zuburi wa bil kitaab' whereas the rest of the qira'at read 'wa zuburi wal kitaab' (ie. without the ba letters). Ibn 'Aamir was Syrian, and it is known that the mushaf that Uthman sent to Syria had the two extra ba letters in it, whereas the other mushafs did not. In this example, an actual word was added in one of the mushafs.
2) Visual inspection: The second way it is known that these mushafs differed from one another is by comparing them. Since the various mushafs are not present anymore, reports must be taken from those who were fortunate enough to have read more than one of the original mushafs of Uthman, or at least knew and reported from those who did. In fact, a number of scholars had written books specially on this topic.
Some authors have mentioned at least ten scholars of the first four centuries of the hijra who had written specific tracts on this topic, amongst them, Al-Kisaa'ee (d. 189 AH), and al-Farraa' (d. 207 A.H). [307] Unfortunately, the only book that remains of these classical works is the work authored by Abdullah ibn Abee Dawood (d. 316 AH), the son of the famous scholar of hadeeth, Aboo Dawood (d. 275 AH), which he entitled Kitaab al-Masaahif. [308]
Khaalid Ibn Iyaas (d. circa 150 AH) reported that he read the mushaf of Uthman and found that it differed with the mushafs of Madeenah in twelve verses, which he quoted. [309] The first of these was 2:132 'wa wasa...' instead of 'wa awsa...' meaning that the first was without an alif, whereas the second was with an alif. This is in the actual script of the mushafs, and it reflected in the differences between the qira'at. Of the ten qira'at, Naafi' and Ibn 'Aamir read it with the alif, whereas the rest do not. In the same way, all of the other differences in the script of the mushaf are still found in the differences between the qiraa'at.
There are more than just twelve differences, though. Khalif ibn Iyaas only compared the mushaf of Uthman with the mushafs of Madeenah. The other mushafs differed from the Madeenah mushaf, as for example in verse 3:184, the mushaf that Uthman sent to Syria had the extra letters, but the others did not. [310]
** These differences, as noted earlier, are only with regards to certian letters and words. There are no verses or phrases that are present in some Mushaf without the others.**
Code:
**Actually, if one reflects over this phenomenon, he will be even more certian that the Qur'aan has been preserved even to the minutest detail. This is so because all of the differences that originated in the different Mushafs of 'Uthman are still found scattered in the various qira'at, showing that the scriptual differences are not accidental, but rather intentional. The Prophet sulAllahu 'alayhi wassalaam used to recite the Qur'an in all of these ways, as will be elaborated upon later.**
**Therefore, the purpose behind these trivial chnages between the mushafs was to preserve the various Ahruf of the Quran**, even to the most minute detail.
303 - Az-Zarqaanee, v.1, p. 262.
304 - Those of 'Aasim, Kisaa’ee, Hamza, Abu ‘Amr and Ibn Katheer.
305 - That of Naafi’ and Ibn 'Aamir.
306 - This point will be better understood after one reads Ch. 11 on the qiraa’at.
307 - cf. Introduction to Ibn Abee Dawood, p. 10.
308 - Unfortunately, the first (and only) person to edit and pubish it was the famous Orientalist scholar Arthur Jeffery (published in Cairo, 1936), as part of his famous work Materials for the History of the Text of the Holy Qur’an, which is discussed in greater detail in Ch. 17.
309 - For these and man more differences, see Ibn Abee Dawood, pps. 37-49.
310 - See al-Hamad, pps. 695-702, where he lists around sixty differences between the various mushafs.