:sl: Respected brother.
There is a hadith about forgetting Quran is a sin but its a weak hadith.here.
“The sins of my ummah were shown to me and there is no sin greater than that of a man who was given or was helped to memorize a surah or an aayah of the Qur’aan and then he forgot it.” but this is a weak hadeeth and was graded weak by Imam al-Bukhari and At-Tirmidhi, and related as such by Albani.
But obviously,a weak hadith does not means a fake hadith.The Quran is a responsibilty Allah SWT sent down on man and we accept it,but then,we forget our responsibility.
(33:72) We offered the trust to the heavens and the earth and the mountains, but they refused to carry it and were afraid of doing so; but man carried it. Surely he is wrong-doing, ignorant.
Majority of us learn about this responsibility but forget.But lets not forget Allah SWT is Arhamar Rahimeen.If you come back,admit your fault and try to correct it,Allah SWT will erase all your sins.Quran and Hadith both are to guide us.The main purpose of these two guidelines is not to learn them by heart and keep them in your heart.They are to learn,understand and practice.
No matter how much you forget,you still have a chance till the last breath.Just say it to yourself that you will learn them and practice them once again and ask Allah SWT to help you,start reading them once again with no burden and tension of memorizing them all in a day and you will see that it was like a mirror covered with dust.You just wipe it off with your hand and here is your image shining in the mirror :statisfie You will memorize them in no time Inshallah.You just have to look at them once again.
And Allah SWT is All Knowing,The most Merciful :statisfie