Why did God/Allah create the foreskin which we are ordered to cut ?

This is an extract from an unpublished work called Sources of Spring, in which there was a dialogue between Sheikh Muhammad Amin Sheiko 1890-1964 and Sir John G Bennet.

Sheikh Muhammad Amin Sheiko answered:

It is well known that the human body consists of flesh, bones and nerves. It is also known that the nervous person`s body does not grow well healthy, and he always remains thin, even if he eats such a lot of food, and increases the number of daily diets.
The embryo in the female`s womb remains in a critical stage in the nine months, because it is in the critical vital forming stage. Since the skin of the penis is a gathering place of very sensitive nerves, it is affected by any friction which causes a general alertness of the nerves in the whole body.
As the place of the embryo in the womb is narrow, to suit the embryo`s size, the embryo is always bent and turned up and its movement increases in the last months. This movement excites the nerves of the skin of the penis, thus the growth of the embryo is hampered because the movements destroy the cells, or leads to a weakness in growth.
So this skin protects this sensitive area from being affected by any shock which causes friction when the embryo moves in the womb, and by that the body attains its safety and perfection.
Exactly as a thermos keeps its contents isolated from the outer factors.
After birth, he enters a new type of life different from his previous one. He is now stretched and there is no friction with the nerves of the skin of the penis. This skin becomes extra and it should be cut because it exists in a glandular area where infection can take place and where dirt and germs may gather under the skin causing acute dermatitis, and infection.
God created the foreskin when the embryo was in the womb of its mother because this organ which Almighty God has made, as an exit for the urine, has made it also, because of its other function composed of a tissue of nervous tissue interconnected deliberately.
Since the end of this organ which is called a skin is very sensitive. If it was exposed to a friction with anything, then that friction will lead to a nervous stress leading to a general stress in the nervous system. It is taken for granted that this stress and sensation will result in a decrease in growth.
Because of that, it is necessary, for the growth of the embryo in his mother`s womb and its completeness, to have a membrane which prevents the head of that organ from what might be in touch or in friction with during the consecutive movement of the embryo in his mother`s womb.
Thus growth is natural and the embryo is born with sound health and body.
Let us now speak about circumcision after birth: 
When the embryo is born and his body`s systems begin to function and the urinary passage begins to do its task, there may be some mold scratch or pathological symptoms, therefore, God the Almighty orders circumcision to protect the body from such troubles.
Therefore, the existence of the skin is necessary for the embryo while it is in its mother`s womb, It denotes the perfection of creation and the marvelous divine discipline. It’s cutting after birth and existing in life is necessary and a mercy from God to man.

Pages 66-70 ,75-76

Source