Only Human Messengers have been Sent
Ad-Dahhak said, reporting from Ibn Abbas;
"When Allah sent Muhammad as a Messenger, the Arabs, or some of them, denied him and said, `Allah is too great to send a human being as a Messenger.'
Then Allah revealed;
أَكَانَ لِلنَّاسِ عَجَبًا أَنْ أَوْحَيْنَأ إِلَى رَجُلٍ مِّنْهُمْ أَنْ أَنذِرِ النَّاسَ
Is it a wonder to people that We have sent Our Inspiration to a man from among themselves (saying);"Warn mankind..." (10;2)
and He said,
وَمَا أَرْسَلْنَا مِن قَبْلِكَ إِلاَّ رِجَالاً نُّوحِي إِلَيْهِمْ فَاسْأَلُواْ أَهْلَ الذِّكْرِ إِن كُنتُمْ لَا تَعْلَمُونَ
And We sent not (as Our Messengers) before you (O Muhammad) any but men, whom We sent Revelation. So ask Ahl Adh-Dhikr, if you know not.
meaning, (ask) the people of the previous Books, were the Messengers that were sent to them humans or angels If they were angels, then you have the right to find this strange, but if they were human, then you have no grounds to deny that Muhammad is a Messenger.
Allah says;
وَمَأ أَرْسَلْنَا مِن قَبْلِكَ إِلاَّ رِجَالاً نُّوحِى إِلَيْهِمْ مِّنْ أَهْلِ الْقُرَى
And We sent not before you (as Messengers) any but men to whom We revealed, from among the people of townships. (12;109)
and not from among the people of heaven as you say."
It was reported by Mujahid from Ibn Abbas that;
what is meant by Ahl Adh-Dhikr is the People of the Book.
This is as Allah says;
أَوْ يَكُونَ لَكَ بَيْتٌ مِّن زُخْرُفٍ أَوْ تَرْقَى فِى السَّمَأءِ وَلَن نُّوْمِنَ لِرُقِيِّكَ حَتَّى تُنَزِّلَ عَلَيْنَا كِتَابًا نَّقْرَءُهُ قُلْ سُبْحَـنَ رَبِّى هَلْ كُنتُ إَلاَّ بَشَرًا رَّسُولاً
وَمَا مَنَعَ النَّاسَ أَن يُوْمِنُواْ إِذْ جَأءَهُمُ الْهُدَى إِلاَّ أَن قَالُواْ أَبَعَثَ اللَّهُ بَشَرًا رَّسُولاً
Say;"Glorified be my Lord! Am I anything but a man, sent as a Messenger!"
And nothing prevented men from believing when the guidance came to them, except that they said;"Has Allah sent a man as (His) Messenger!" (17;93-94)
وَمَأ أَرْسَلْنَا قَبْلَكَ مِنَ الْمُرْسَلِينَ إِلاَّ إِنَّهُمْ لَيَأْكُلُونَ الطَّعَامَ وَيَمْشُونَ فِى الاٌّسْوَاقِ
And We never sent before you (O Muhammad) any of the Messengers but verily, they ate food and walked in the markets. (25;20)
وَمَا جَعَلْنَـهُمْ جَسَداً لاَّ يَأْكُلُونَ الطَّعَامَ وَمَا كَانُواْ خَـلِدِينَ
And We did not create them (the Messengers, with) bodies that did not eat food, nor were they immortals. (21;8)
قُلْ مَا كُنتُ بِدْعاً مِّنَ الرُّسُلِ
Say (O Muhammad);"I am not a new thing among the Messengers." (46;9)
قُلْ إِنَّمَأ أَنَاْ بَشَرٌ مِّثْلُكُمْ يُوحَى إِلَىَّ
Say (O Muhammad);"I am only a man like you. It has been revealed to me." (18;110)
Then Allah informs those who doubt that a Messenger can be a human to ask those who have knowledge of the previous Scriptures about the Prophets who came before;were their Prophets humans or angels!
Then Allah mentions that He has sent them