Tafsir of Hud 11:25

The Story of Nuh and His Conversation with His People Allah, the Exalted tells;

ولقد أرسلنا نوحا إلى قومه

And indeed We sent Nuh to his people (and he said): Allah, the Exalted, informs about Prophet Nuh. He was the first Messenger whom Allah sent to the people of the earth who were polytheists involved in worshipping idols. Allah mentions that he (Nuh) said to his people,

إني لكم نذير مبين

I have come to you as a plain warner. meaning, to openly warn you against facing Allah's punishment if you continue worshipping other than Allah. Thus, Nuh said,