﴿ أَمْ يَقُولُونَ ٱفْتَرَىٰهُ ۚ بَلْ هُوَ ٱلْحَقُّ مِن رَّبِّكَ لِتُنذِرَ قَوْمًۭا مَّآ أَتَىٰهُم مِّن نَّذِيرٍۢ مِّن قَبْلِكَ لَعَلَّهُمْ يَهْتَدُونَ ﴾

“and yet, they [who are bent on denying the truth] assert, “[Muhammad] has invented it!” Nay, but it is the truth from thy Sustainer, enabling thee to warn [this] people to whom no warner has come before thee, so that they might follow the right path.”

Or do they say ‘He Muhammad (s) has invented it’? Nay but it is the truth from your Lord that you may warn thereby a people to whom no warner came before you mā is for negation that perhaps they may find right guidance by your warning.