The word(s) "assert" appears 3 time(s) in 3 verse(s) in Quran in Saheeh International translation.

(1) And they attribute to Allah that which they dislike, and their tongues assert the lie that they will have the best [from Him]. Assuredly, they will have the Fire, and they will be [therein] neglected.

(سورة النحل, An-Nahl, Chapter #16, Verse #62)
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(2) So do not assert similarities to Allah. Indeed, Allah knows and you do not know.

(سورة النحل, An-Nahl, Chapter #16, Verse #74)
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(3) And do not say about what your tongues assert of untruth, "This is lawful and this is unlawful," to invent falsehood about Allah. Indeed, those who invent falsehood about Allah will not succeed.

(سورة النحل, An-Nahl, Chapter #16, Verse #116)
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