The Spider - 29:48
You did not read any of the previous books, nor did you write them with your hand. In that case, there would have been a pretext for those who advocate falsehood to be suspicious.
Prophet Muhammad's people had not received any warning for a long time:
Sheva/34:44
We had not given them a Book to study, nor had We sent them a warner before you.
The Ornaments of Gold/43:21
Did We give them a Book before this that they rely on it?
The Cattle/6:155
And this is a blessed Book which We have sent down. So you should follow it and act righteously so that mercy may be shown to you.
The Cattle/6:156
"So do not say, "Two groups before us were given the Book, but we were ignorant of their teachings"."
The Cattle/6:157
"Nor can you say, "If the Book had been sent down to us, we would have been on a more right path than them". There has come to you a proof from your Lord, a guidance and a mercy. Who is more unjust than he who denies the signs of Allah and turns away from them? We will punish those who turn away from Our Verses with the worst of torment for their turning away."
The Family Of Imran/3:20
"If they dispute with you, say, "I and those who follow me have submitted ourselves to Allah."Say to those who have been given the Book and those who have not been given the Book, "Have you submitted?"If they submit, they will find the truth. If they turn away, your duty is only to announce. Allah sees the servants."
The Cattle/6:92
This is a blessed Book which confirms what was before it, and it has been sent down that you may warn the mother of countries and those around you. Those who believe in the Hereafter believe in it and they keep up their prayers.
The Stories/28:46
Nor were you on the slope of Tur when We called out (to Moses). But (We inform you) as a mercy from your Lord that you may warn a people to whom no warner came before you, that they may take heed.
Yaseen/36:5
This is a revelation sent down by the Most High and Most Merciful.
Yaseen/36:6
That you may warn a people who have remained totally ignorant because their forefathers were not warned.
Council/42:7
Thus do We reveal to you a Qur´an in a perfect language so that you may warn the capital city and its environs and warn them of the Day of Gathering which is to come. Some of them will enter Paradise and some will enter Hell.
The Ornaments of Gold/43:5
Shall We stop conveying the Message to you because you are a transgressing people?
The Believers/23:68
Have they not examined the Word, or has something come to them which did not come to their ancestors of the past?
The Cow/2:198
It is permissible for you to seek the favor of your Lord (by trading in the Hajj region). When you leave Arafat, remember Allah in the Holy Place. Remember Him because He has guided you; before that you were astray.
The Congregation - Friday/62:2
He it is Who has sent a Messenger from among the Ummah, one of their own, who recites to them His verses, purifies them and teaches them the Book and wisdom. Before that they were in manifest error.