The Quran

وَمَن أَظلَمُ مِمَّنِ افتَرىٰ عَلَى اللَّهِ كَذِبًا أَو قالَ أوحِيَ إِلَيَّ وَلَم يوحَ إِلَيهِ شَيءٌ وَمَن قالَ سَأُنزِلُ مِثلَ ما أَنزَلَ اللَّهُ ۗ وَلَو تَرىٰ إِذِ الظّالِمونَ في غَمَراتِ المَوتِ وَالمَلائِكَةُ باسِطو أَيديهِم أَخرِجوا أَنفُسَكُمُ ۖ اليَومَ تُجزَونَ عَذابَ الهونِ بِما كُنتُم تَقولونَ عَلَى اللَّهِ غَيرَ الحَقِّ وَكُنتُم عَن آياتِهِ تَستَكبِرونَ

Muhammad Asad

And who could be more wicked than he who invents a lie about God,¹ or says, "This has been revealed unto me," the while nothing has been revealed to him? - or he who says, "I, too, can bestow from on high the like of what God has bestowed"?² If thou couldst but see [how it will be] when these evildoers find themselves in the agonies of death, and the angels stretch forth their hands [and call]: "Give up your souls! Today you shall be requited with the suffering of humiliation for having attributed to God something that is not true, and for having persistently scorned His messages in your arrogance!"

In this context, the "lie" would seem to refer to the denial, spoken of in verse 91, of the fact of divine revelation as such.
Implying, in a sarcastic manner, that the purported revelation has in reality been composed by a human being and that, therefore, the like of it can be produced by other men.