The punishment of one who learns the Quran and then forgets it

It is narrated from Sayyiduna Abu Hurayrah and Sayyiduna Ibn Abbas (may Allah be pleased with them) that the Messenger of Allah (peace and blessings be upon him) delivered a sermon to us; then the narrator mentioned the complete hadith, in which there was also this (saying): "Whoever learned the Qur'an and then deliberately forgot it will meet Allah Almighty in the state of a leper, bound in collars and chains, and for every verse of the Qur'an (which he forgot) Allah Almighty will set upon him a snake that will keep biting him in the Fire of Hell. Whoever acquired knowledge of the Qur'an but did not act upon it, and preferred over it the worthless goods of the world and its outward adornment, has become deserving of Allah Almighty's severe displeasure and wrath, and his rank will be like that of the Jews and Christians who cast the Book of Allah behind their backs and sold it for a paltry price. Whoever recited the Qur'an merely for show, fame and the pursuit of worldly status will meet Allah Almighty in such a state that his face will be mere bone without a trace of flesh upon it, and the Qur'an will push him by the nape of his neck into the Fire, so that he falls into the pit of Hell along with those who fall. And whoever recited the Qur'an but did not act upon it, Allah Almighty will raise him blind on the Day of Resurrection, and he will say: 'My Lord, why have You raised me blind when I used to see (in the world)?' [Surah Ta Ha: 125]. Allah, the Lord of Might, will say: 'Thus did Our signs come to you and you forgot them, and thus today you will be forgotten' [Surah Ta Ha: 126]; then a command will be given and he will be taken to the Fire. Whoever learned the Qur'an for the pleasure of Allah Almighty and to gain understanding of the religion of Allah will have as much reward as Allah Almighty has given to all the angels, prophets and messengers. But whoever learned the Qur'an for show, renown, to dispute with the foolish, to boast over the scholars and to seek the world, Allah Almighty will scatter his bones on the Day of Resurrection; he will be among the people suffering the severest punishment, and because of Allah's severe punishment and wrath there will be no kind of punishment that he is not made to taste."
Al-Harith said: Dawud bin al-Muhabbar narrated to us, from Maysarah bin Abd Rabbih, from Abu A'ishah al-Sa'di, from Yazid bin Amr, from Abu Salamah bin Abd al-Rahman, and he from Sayyiduna Abu Hurayrah and Sayyiduna Ibn Abbas (may Allah be pleased with them), this narration.

It is narrated from Abu al-Aliyah (may Allah have mercy on him) that he said: "We used to count among the greatest and gravest of sins that a man should learn the Noble Qur'an and then become heedless of it, neglecting its recitation and revision, until he forgets it."
Imam Ahmad bin Hanbal (may Allah have mercy on him) recorded it in 'Kitab al-Zuhd'.

It is narrated from Abu Kinanah (may Allah have mercy on him) that Sayyiduna Abu Musa al-Ash'ari (may Allah be pleased with him) gathered those who had memorised the Qur'an, and they numbered close to three hundred. He spoke of the greatness and rank of the Noble Qur'an and then said: "This Qur'an is indeed a source of reward for you, a treasure (for the Hereafter) for you, and (if your deeds go astray) a burden upon you as well. So follow the Qur'an and do not make the Qur'an follow you, for whoever follows the Qur'an, it will bring him down into the lush gardens of Paradise; and whoever the Qur'an follows (that is, whoever casts the Qur'an behind his back while the Qur'an demands its rights from him), it will push him by the nape of his neck and fling him into the Fire."
The chain of this report is jayyid (good).

It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that he said: "I dislike that a reciter of the Noble Qur'an should be fat and heavy-bodied (from being absorbed in worldly comforts)."
The narrator said: Then I mentioned this to Imam Ibrahim al-Nakha'i (may Allah have mercy on him), and he explained that the actual words of Sayyiduna Abdullah (may Allah be pleased with him) were: "I strongly dislike that I should see a reciter who is fat and well-fed (out of heedlessness and luxury) and who forgets the Qur'an."

It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that he said: "Do not set one part of the Book of Allah against another (that is, do not try to establish contradiction and conflict between the verses of the Qur'an), for this indeed causes doubt and uncertainty to arise in your hearts."
[Takhrij: al-Musannaf of Ibn Abi Shaybah: 3505; its chain is sahih (authentic).]

It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) said: "Do not dispute about the Noble Qur'an (its verses and its truths), for unwarranted argument and wrangling about it is disbelief."
Al-Tayalisi recorded this hadith in his Musnad, and by virtue of its supporting reports (shawahid) it reaches the level of sahih (authentic).