(From the Kastamonu Addendum page-134)
…
A young hâfidh among the students of the Risale-i Nur said, like many other men, “The sickness of forgetfulness increases in me. What should I do?” I told him: Do not look at non-mahrams as much as possible because there is a riwâyât on this. As Imam Shafi (ra) has said, “Looking at what is haram causes forgetfulness.” Yes, among the people of Islam, as haram look1 increases, desires of the nafs will be excited and will cause one to waste (israf) through the misuse of body. He will be obliged to take ghusl a few times a week as a result of it, and will medically experience a weakness in his faculty of memory.
Yes, in this age, particularly in these warm countries, the misuse arising from evil looks due to the immodest clothing begins to result in a general sickness of forgetfulness. Whether minor or major, everyone in general voices this complaint. Thus, with the rise of this general sickness, the tip of the ta’wîl of striking news given by the noble hadith is seen. The Prophet (asm) decreed, “In the âkhirzaman, the Qur’an will be torn away, lifted from the hearts of hâfidhes and be forgotten.” That is, this sickness will intensify, and for some people, the memorisation of the Qur’an will be barred due to these evil looks; it will demonstrate the ta’wîl of this hadith.لاَ يَعْلَمُ الْغَيْبَ اِلاَّ اللّٰهُ .
…
1 (Looking at non-mahrams.) (Tr.)