The Table Spread - 5:19 "People of the Book! Our apostle has come to you after a period of gap between the apostles, and he is telling you the truth so that you may not say: "There has not come to us a bearer of glad tidings and a warner". Behold, a bearer of glad tidings and a warner has come to you. Allah is the Almighty."
Prophet Muhammad's community did not receive any message or messenger for a long time:
The Table Spread/5:19 "People of the Book! Our apostle has come to you after a period of gap between the apostles, and he is telling you the truth so that you may not say: "There has not come to us a bearer of glad tidings and a warner". Behold, a bearer of glad tidings and a warner has come to you. Allah is the Almighty."

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."

Yaseen/36:6 That you may warn a people who have remained totally ignorant because their forefathers were not warned.

Sheva/34:44 We had not given them a Book to study, nor had We sent them a warner before you.

The Prostration/32:3 "Do they say, "He has fabricated it"? But this is a truth from your Lord, that you may warn a people to whom no warner has reached before you, that they may be guided."

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.