The eyes of the Holy Prophet were matchless in their outward beauty as well as in their vision and sight. Ibn Abbas in describing his beauteous eyesight states:
The Holy Prophet could see equally well during the darkness of the night and the brightness of the day. (Bukhari)
Anas narrates: The Holy Prophet himself said:
O people! I am your Imam.Do not precede me in ruku` and sajda because in addition to seeing what is in front of me I also see what is behind me. (Muslim)
Abu Huraira similarly narrates the Prophet's words:
I swear on Allah Almighty, neither your ruku` is hidden from me nor your sajda because I can see you behind my back as well. (Muslim and Bukhari)
The gist of the commentary which the great scholar Sheikh `Abd al- Haqq Muhaddith Dehlvi has written on these traditions is as follows:"Only Allah Almighty exactly knows the truth [i.e. the extent] of his vision. In addition, every blessed limb too falls in this category [of piercing sight], because no one can fully understand what they were." They are without doubt beyond one's imagination and intellect. Any assumption falls short of their virtuosity. Allah Almighty has full Power to bestow vision to every part of the body, or grant this unique sight as His Favour and Grace on His beloved Messenger.
If by this sight is meant vision of the heart, then it is that knowledge which was bestowed upon him by Allah Almighty.
Some people tend to incorrectly rely on the inauthentic tradition whereby the Holy Prophet said: "I do not know what is behind the wall." No origin is known (la asl) for such a hadith. Even if such an improbable saying were attributable to the Prophet, then its purpose would to show personal humility and not to negate such knowledge. The meaning would then be: "I do not know that on my own, nor do I have such knowledge on my own," but as far as Bestowed Knowledge is concerned, i.e knowledge given by Allah Almighty, the Holy Prophet was fully equipped with it by his Creator.
The Holy Qur'an bears the testimony to this:
And We granted you knowledge of what you knew not, and the bounty of Allah for you has been infinite. (4:113)