This report was mentioned by al-Qurtubi in al-Jaami’ li Ahkaam al-Qur’aan (1/92) and Ibn Katheer in his Tafseer (1/18), narrated from Wakee’ from al-A’mash from Abu Waa’il from Ibn Mas’ood (may Allaah be pleased with him); it is the words of Ibn Mas’ood, not of the Prophet (blessings of Allaah be upon him).
This isnaad is saheeh from Wakee’ to Ibn Mas’ood.
Although al-A’mash is mudallis, what he narrated from those with whom he spent a great deal of time and narrated a great deal from them, such as Ibraaheem al-Nakha’i and Abu Waa’il, may be accepted.
Al-Dhahabi said in his biography of al-A’mash in Mizaan al-I’tidaal (2/224):
He is mudallis (i.e., gives a false impressions concerning the narration of the hadeeth, using ambiguous words to give the impression that he heard it directly from his Shaykh when that is not the case), and sometimes he narrates in this manner from a weak narrator without realising it. When he says haddathana [he told us], there is no problem with that, but when he says ‘an [narrating from], there is the possibility of tadlees except in the case of narration from the shuyookh from whom he narrated a great deal, such as Ibraaheem, Abu Waa’il [in the printed version it says “Ibn Abi Waa’il” but this is an error; the word “Ibn” is a mistake] and Abu Saalih al-Sammaan. His narration from these shaykhs is to be understood as meaning that he heard directly from them and there is no interruption in the chain. End quote.
But there remains the issue of the narrators who come after Wakee’. Al-Qurtubi and Ibn Katheer do not mention the isnaad in its entirety, and perhaps it is because of this that al-‘Allaamah Ahmad Shaakir omitted it from his abridgement of Ibn Katheer’s Tafseer which is entitled ‘Umdat al-Tafseer, in the introduction to which (1/11) he stated that he omitted every weak or problematic hadeeth.
But al-Suyooti attributed it in al-Durr al-Manthoor (1/26) to Wakee’, and Imam Wakee’ ibn al-Jarraah wrote a well known Tafseer.
See: al-Majma’ al-Mu’assis by al-Haafiz Ibn Hajar (p. 113)
If that is proven, then the isnaad is saheeh, and the report from Ibn Mas’ood (may Allaah be pleased with him) is saheeh.
And Allaah knows best.