What is the evidence from the Qur'an and Sunnah that the Qur'an is the word of Allah?

Among the clearest proofs that the Qur'an is the Word of Allah the Almighty is His saying: "And if anyone of the polytheists seeks your protection, then grant him protection so that he may hear the Word of Allah," and what is meant here is the Qur'an. Also, the saying of the Messenger of Allah, peace and blessings be upon him: "Is there not a man who will take me to his people, for the Quraysh have prevented me from conveying the Word of my Lord?" and what is meant here is the Qur'an.