(The Holy Qur'an, Al –Baqarah, 2:22). This is a clear indication of Allah's glory. Despite this, the Qur'an is inundated with examples of people who refuse to accept the words of the Prophet and thus deny the existence of Allah. Man can literally see the wonders of the world that he is physically immersed in, yet he cannot see that this is a byproduct of the glorious nature of Allah. .
This is a criticism of the limiting nature of solely living in the physical world. Man appreciates and flourishes as a result of these "Fruits for your Sustenance," but he fails to reach a greater level of consciousness by not understanding the true nature of these blessings. He is too fixated upon his bounty and blindly harvests the benefits of Allah: "on their eyes is a veil; Great is the penalty they (incur)." (The Holy Qur'an, Al-Baqarah, 2:7). Over indulgence in the material world acts as a "veil" upon the eyes of man, only permitting him to perceive the material wonders of the world. This "veil" is preventing man from seeing down the path to Allah. Consequently, when man is engrossed in the physical world he is led "astray." .
Allah seeks to empower man and teach him how to remove this veil before his eyes by training him to acknowledge the spiritual world. The Qur'an acknowledges that "If (such) were Our Will. We could send down to them From the sky a Sign to which they would bend their necks in humility." (The Holy Qur'an, Al Shu'ara, 26:4). Allah's all-powerful nature makes him capable of removing any doubt of his existence in the eyes of the non-believers. By sending "From the sky a sign," Allah would be able to enlighten humanity via the means that man truly understands, the literal world, and gain his worship. However, he deliberately chooses not to do this. In fact Muhammad preaches, "By command of my Lord: Of knowledge it is only A little that is communicated to you (O Men!) (The Holy Qur'an, Al Isra, 17:85).