Human beings have limited capacities of sight, sound, hearing, experience and intellect. It is a fact of life that our abilities are not all-powerful. For example, out of the whole electromagnetic spectrum all that human beings are capable of visualizing are the wavelengths between 400 and 700nm. This we call “visible” light. Bees on the other hand are able to see ultraviolet radiation markings on flowers, which guide them to nectaries. Cobras are able to see infrared radiation that warm bodies give off. This allows them to see animals in what is pitch dark to us.
As for our audible abilities, we can hear sounds in the range of 20 Hz to 20,000 Hz. We cannot hear sounds that are above or below this range. Dogs on the other hand can detect frequencies as high as 45,000 Hz, cats as high as 85,000 Hz, bats 120,000 Hz and dolphins an amazing 200,000 Hz. While dogs, cats, bats, and dolphins have an unusual ability to detect ultrasound, an elephant possesses the unusual ability to detect infrasound of a frequency as low as 5 Hz. Similar is the case of the limitations of our sense of smell and abilities in general. It is no wonder that Allah says: “He knows all that is beyond the reach of a created being's perception as well as all that can be witnessed by a creature's senses or mind - the Great One, the One far above anything that is or could ever be!” (Al-Quran 13:9)
Earlier nations used to pester their prophets to ask Allah (subhana wa ta'ala) all kinds of questions. Allah (subhanahu wa ta’ala) says that this resulted in their getting answers that they were not capable of understanding with their limited intelligence and knowledge. As a result of this they turned to disbelief after having experienced belief.
Imagine a flat two dimensional worm that sees and moves in only two directions: forward-backward, right-left. It has no concept of up and down. Should an apple begin to descend into its plane of existence, what would it see?
The worm would see a red point that slowly begins to expand. It mysteriously grows larger and larger. Then as the apple begins to descend through the plane of the worm’s existence, the red expanding circle begins to contract until it becomes a point again and disappears. Once the apple is below the plane that the two dimensional worm exists in, it has disappeared from the worm’s sight. Should the apple speak to the worm, the worm would hear something but not know where the sound is coming from. Were the apple to try to explain its shape to the worm, would the two-dimensional worm be able to make any sense of it? We too should accept our limitiations and not deny ourselves belief because Allah has withheld some knowledge from us.