The script and spellings evolve, and later development looks at the previous writing as an error. At some places in the Quran, the old script of Arabic in the Quran was not changed and kept as it is to commemorate the original Uthmanic script. A scholar, Mufti Zahid’s response to it is:
Writing “لنسفعا” with an alif instead of nun is neither a grammatical mistake nor a spelling error. During that time, the “Nun of Emphasis” (نون تأکید خفیفہ) was not only written in the form of an alif, but it was also pronounced as alif, especially when pausing. Here are two verses from the poem of the renowned Arab poet of that era, Al-A’sha Al-Hamdani, as an example:
“Wadha an-nasba al-mansoob la tansakanah,
Wa la ta’bud al-awthana wallaha fa’budaa”
“Wa sabbih ‘ala heena al-‘ashiyyati wal-duha,
Wa la tahmad ash-shaytana wallaha fa’hmidaa”
In reality, the poet wanted to say “fa’ubdan” and “fa’hamdan”, but not only did he write it as alif, but it was also pronounced as alif because the rhyme throughout the poem follows the pattern of dal with alif. Abu Hayyan Al-Andalusi, while interpreting the verse “وَلَيَكُونًا مِّنَ الصَّاغِرِينَ” (Surah Yusuf, 12:32), cited the first verse from the aforementioned lines of Al-A’sha. Therefore, from a syntactic perspective, this citation is valid.
In fact, during that period, some words were written in different forms. For the Qur’an, certain styles were adopted for some reasons— sometimes one form, and sometimes another. However, all forms were correct according to the orthography of that time.
What happened later is that the Muslim community allowed the general Arabic orthography to evolve naturally, but the Qur’anic orthography was halted and paused. As the common writing style began to differ from Qur’anic orthography over time, books were written on the subject of Qur’anic script. Consequently, several branches of knowledge emerged focused solely on Qur’anic writing, for instance, volumes of books on Rasm (Qur’anic orthography), such as Nathr al-Murjan (which possibly has seven volumes) and Mukhtasar al-Tabyin (which might have four volumes).
Thus, one should neither oversimplify every matter nor take the intellectual heritage of this Ummah lightly.