There is a chapter in the Quran called Maryam (Mary) in which the mother of Jesus is eulogized in a way not even found in the bible. At the same time, there is no chapter in the name of Muhammad's wife Aisha or his daughter Fatemah. The name of prophet Isa (Jesus) is mentioned 25 times in the Quran while the name of prophet Muhammad is mentioned only five times.
If you were in the situation of prophet Muhammad while he and Abu-Bakr were inside the cave of hira surrounded by the unbelievers who could have seen them if they had just looked down. The human reaction would be to search for a back exit or some other way out or to shush in order not to be heard. However, the prophet told Abu-Bakr "Grieve not; surely Allah is with us." (Quran 9:40). This is not the mentality of a deceiver; it is the mentality of a prophet who has the confidence that God would certainly take care of him.
Surah Al-Masad (Palm Fibres) was revealed ten years before the death of Abu-Lahab, the prophet's uncle. It said that Abu-Lahab and his wife will die unbelievers and will be in the hellfire. They could have easily proved the Quran to be wrong by accepting Islam. But, they did not believe or even pretend to believe. How could the prophet be that confident unless he was sure that the Quran was God's revelation?
Commenting on the verse: "That is of the tidings of the unseen that we reveal to you; in no way did you (yourself) know it, neither your people, even before this. So endure patiently; surely the end is for the pious." (Quran 11:49). Miller writes that none of the scriptures uses this kind of style; that is, giving the reader the piece of information and then telling him it is new information. It is really a unique challenge. What if the people of Makkah, even by pretense, had said they knew that before? What if one scholar discovered later that this information was already known before? However, this did not happen.
Professor Miller mentioned what contemporary Catholic Encyclopedia includes under the entry of Quran. It mentions that despite the plethora of studies, theories, and attempts to attack the veracity of Quranic revelation under many pretexts, none of them can be logically adopted. The Church itself did not dare to adopt any of such theories but at the same time it did not admit the truthfulness of the Muslims' theory that the Quran is, without doubt, the last heavenly revelation.