Abu Waqid reported,
We used to come to the Prophet ﷺ whenever revelation was sent down to him, and he would relate it to us. One day he said to us, "Allah 
has said, 'We sent down wealth for the establishment of prayer and the giving of zakat. If the son of Adam had a valley, he would love to have a second one beside it, and if he had two valleys, he would love to have a third. Nothing fills the belly of the son of Adam except dust, then Allah turns in mercy to whoever repents.'"
Azami 15264
Hasanعن أبي واقد الليثي قال
كنا نأتي النبي ﷺ إذا أنزل عليه فيحدثنا، فقال لنا ذات يوم: إن الله عز وجل قال: إنا أنزلنا المال لإقام الصلاة، وإيتاء الزكاة، ولو كان لابن آدم واد لأحب أن يكون إليه ثان، ولو كان له واديان لأحب أن يكون إليهما ثالث، ولا يملأ جوف ابن آدم إلا التراب، ثم يتوب الله على من تاب.
Ahmad narrated it (21906), and Tabarani in al-Kabir (3/279), both through Hisham bin Saad, from Zayd bin Aslam, from Ata bin Yasar, from Abu Waqid Laythi, who related it. Its isnad is hasan because of Hisham bin Saad, for his hadith is hasan when he narrates from Zayd bin Aslam, since he is among the most reliable narrators regarding him.The summary of the matter concerning these hadiths is that his saying, "If the son of Adam had a valley..." is not part of the Quran, and the assumption of some companions does not make it part of the Quran, because the Quran cannot be established by mere assumption, as they said. It is possible that it is as they assumed, and that abrogation occurred in it, both in recitation and in writing, and that what is abrogated from the Quran does not require tawatur, since tawatur is only required for what exists between the two covers of the Mushaf.Qurtubi said in al-Mufhim (3/93) regarding his saying, "We used to recite a surah that we likened in length and severity to Baraah, but I was made to forget it," this is a type of abrogation, for abrogation, according to what our scholars have transmitted, is of three kinds.The first is the abrogation of the ruling while the recitation remains. The second is the opposite, the abrogation of the recitation while the ruling remains. The third is the abrogation of both the ruling and the recitation, like the removal of these two surahs mentioned by Abu Musa, for both their ruling and their recitation were removed.This abrogation is what Allah Almighty referred to when He said, "Whatever verse We abrogate or cause to be forgotten" [Baqarah 2:106], according to the reading of one who reads it with the nun vowelled with damma and the sin with kasra. Likewise His saying, "We will make you recite, so you will not forget, except what Allah wills" [Ala 87:6–7], and these two surahs (meaning the surah that was like Baraah, and the surah that was like the musabbihat) are among what Allah Almighty willed to make him forget after He had already revealed it, and this is because Allah Almighty does whatever He wills, and is capable of whatever He wills, since all of that is possible.Let no one imagine from this or anything similar that something has been lost from the Quran, for that is false, as is proven by His saying, "Indeed, it is We who sent down the message, and indeed, We will be its guardian" [Hijr 15:9], and by the fact that the consensus of the companions and those who came after them was established that the Quran, which we are commanded to worship through its recitation and its rulings, is what is fixed between the two covers of the Mushaf, without addition or omission, as we have established in the principles of jurisprudence. End of his statement.