salam,
i visited the link and it just says it is unauthentic, doesnt say why or how, doesnt show the weakness in the sanad, just saying something is unauthentic is not good enough, you need reasons and proof as well.
i have already found an answer to this one: `Abdullah b. `Umar reportedly said, 'Let none of you say, "I have got the whole of the Qur'an." How does he know what all of it is? MUCH OF THE QUR'AN HAS GONE. Let him say instead, "I have got what has survived."' (Jalal al Din `Abdul Rahman b. Abi Bakr al Suyuti, al-Itqan fi `ulum al-Qur'an, Halabi, Cairo, 1935/1354, Volume 2, p. 25)
firstly this hadith has been put in al suyutis book in the section: Section forty-seven: About the Abrogating and the Abrogated, Al-Itiqan fil Uloom al-Quran, Haeya al-Masriya al-‘Aamah lil-Kitab, Egypt 1974 vol.3 p.66, 82-83
and this is not the only time he quotes this hadith, he also quotes it again and again he puts it under the chapter heading of the abrogation: Mu'tarik al-Aqran fi Aijaz al-Qur’an, Dar al-Kotob Al-Ilmiyah, Beirut, 1988 vol.1 p.95
this hadith al suyuti quotes is originally from the works of In Abu ‘Ubayd’s (d. 228 A.H.) and he again puts it under his title of abrogation: “[About] what all was abrogated from the Qur’an after revelation and is not put in the Masahif.”Fada’il al-Qur’an, Dar Ibn Kathir, Damascus, 1995 vol.1 p.320
Most important is the narration quoted by Hafiz Ibn Hajr (d. 852 A.H.) which compliments and fixes the meaning of the report we are discussing. Ibn Hajr writes;
وقد أخرج بن الضريس من حديث بن عمر أنه كان يكره أن يقول الرجل قرأت القرآن كله ويقول إن منه قرآنا قد رفع
Ibn al-Dhurays has narrated a report of Ibn Umar that he used to dislike the person who said, ‘I have recited the whole of the Qur’an.’ He (Ibn Umar) used to say, ‘But (the reality is) a part of the Qur’an has been abrogated.’ Fath al-Bari, Dar al-Ma’rifah, Beirut 1379 A.H. vol.9 p.65
This report seals the fact that Ibn Umar’s statement simply refers to what was abrogated from the Qur’an. so when someone today says i have read the WHOLE of the quran. Ibn umars claim is that you have read the whole quran which allah swt intended to preserve, but the abrogated parts (like the verse of stoning, and the verse of breastfeeding) you have not read, and not all of the abrogated parts you have read. So you may have read everything that is in the quran, but you havent read all of the abrogated verses such as the verse of stoning, of breastfeeding and all other revelation that wasnt intended to be in the quran for eternitiy, but rather was supposed to be abrogated. That is why this quote keeps coming under chapter headings: abrogation
Abu Bakr ibn Tayyib Al-Baqilani (d. 403 A.H.) in his amazing work al-Intisar li’l-Qur’an (In Defence of the Qur’an), quotes another narration on the similar lines and then explains the two together. He writes;
ونحوُ روايةِ عبدُ الله بنُ عباسِ عن أبي أنه سمعه وقد قال له رجل: "يا أبا المنذر إني قد جمعت القرآن، فقال له: ما يدريكَ لعله قد سقطَ قرآن كثير فما وُجد بعد".
And similar is the report of Abdullah bin ‘Abbas from Ubay, that he heard a man said to him; ‘O Abu al-Munzar verily I have gathered (i.e. memorized) the whole of the Qur’an.’ He (Ubay) said to him, ‘He does not know (what the whole of it was) because so much of the Qur’an was abrogated and it was not found afterwards.’[5]
And then explaining it he writes;
“And it is not possible for anyone to claim that he has learnt (all) what was revealed as Qur’an- the abrogating part of it and the abrogated. And their words ‘it was not found afterwards’ (underscore) that we do not find in our day one who has memorized all that was abrogated and whose recitation was given up. And this is something which was bound to happen.” [6]
this is a shorter explanation of this hadith.
if you want a full refutation visit the following links:
http://icraa.org/meaning-of-ibn-umars-statement-much-of-the-quran-is-gone/http://www.letmeturnthetables.com/2012/10/ibn-umar-irreparable-much-quran-loss.html#tab2also according to another site:
It is reported from Ismail ibn Ibrahim from Ayyub from Naafi from Ibn Umar who said: "Let none of you say 'I have acquired the whole of the Qur'an'. How does he know what all of it is when much of the Qur'an has disappeared? Rather let him say 'I have acquired what has survived.'" (as-Suyuti, Al-Itqan fii Ulum al-Qur'an, p.524).
This reference to the Itqan is untraceable as no edition of it is in less than two volumes to my knowledge.
The above refers to a famous saying of Ibn `Umar, once again deceptively/ignorantly mistranslated so as to mislead readers to think it means other than its actual meaning.
The words used by Ibn `Umar for the terms given as "acquired," "disappeared," and "what has survived" above were -- I am quoting from memory -- respectively "ahattu" (I have encompassed), "faatahu" (escapes him), and "ma tayassara minhu" (whatever amount of it has been facilitated). The actual meaning of Ibn `Umar's words is:
"Let no one say: I have encompassed the whole of the Qur'an [= its meanings]. How does he know what all of it is when much of the Qur'an escapes him? Rather, let him say: I have encompassed whatever amount of it has been facilitated [for me to know]."
Ibn `Umar was famous for his strictness in refraining from interpreting the Qur'an, even criticizing Ibn `Abbas's interpretive zeal in the beginning, then accepting its authority. He was not referring to the collection of the Qur'an! But only to the ethics of the exegete, in the same line as Ibn `Abbas's saying narrated by al-Tabari and cited by al-Suyuti and al-Zarkashi: "There are ambiguous verses in the Qur'an which no one knows besides Allah. Whoever claims that he knows them, is a liar."