That you may warn a people whose forefathers were not warned, so they are unaware. ( Ya-Sin : 6)
It says here that the ancestors of the Arabs were neglected. But didn't the message of the Torah reach them? They knew about the Torah and the Gospel, since there were many Jews and Christians among the Arabs.
But when the truth came to them from Us, they said, "Why was he not given like that which was given to Moses?" Did they not disbelieve in that which was given to Moses before? They said, "[They are but] two works of magic supporting each other, and indeed we are, in both, disbelievers." ( Al-Qasas : 48)
And besides, it is said that every nation has its own mentor, that is, the one who guides them on a straight path.
And those who disbelieved say, "Why has a sign not been sent down to him from his Lord?" You are only a warner, and for every people is a guide. ( Ar-Ra'd : 7)
Verses 16:36 and 6:130 say that messengers were sent to every nation. If this is so, then it means that the ancestors of the Arabs knew about the teachings of the messengers. Then why does 36:6 say they didn't know about it?
And We certainly sent into every nation a messenger, [saying], "Worship Allah and avoid Taghut." And among them were those whom Allah guided, and among them were those upon whom error was [deservedly] decreed. So proceed [i.e., travel] through the earth and observe how was the end of the deniers. ( An-Nahl : 36)
"O company of jinn and mankind, did there not come to you messengers from among you, relating to you My verses and warning you of the meeting of this Day of yours?" They will say, "We bear witness against ourselves"; and the worldly life had deluded them, and they will bear witness against themselves that they were disbelievers. ( Al-An'am : 130)
How does this fit in with verse 36:6, that no one admonished the Arab fathers and that they were in ignorance?