The benefits of circumcision outweigh the pain
Question

                First I would like to thank you for
      operating such a service over the internet. I live in a relatively isolated part of the
      U.K and have had no joy from trying to get an answer to my query from the main Mosque in
      the U.K (Regents Pk. Mosque).
    I am a Muslim happily married to an English lady. We have a 9 month old
      baby boy. The time has come for me to decide whether or not he should have circumcision
      performed. I have read your previous replies about circumcision, from which I got my first
      answer that circumcision is 'Sunnah' and not farz. On a medical point of view I know that
      it is very hygienic if a person has circumcision and those without can experience
      infections etc. in later life. But this cannot be used as justification because it can be
      also argued that a persons appendices or toneless should be removed at birth because of
      the chance of them causing a problem in later life. My reasons of yes 'it is Islamic to
      have circumcision' are sometimes outweighed by 'why should I cause a young 9 month old
      baby pain'.What in your mind are the implications of not having cicumcision performed on
      my son for the sole reason that I will be causing a small defenseless boy pain like he has
      not experienced before?. How does Allah justify such pain? 
   I know that you are busy and you can't always reply to questions, but
      please put my question in a que if neccesary, but please do reply because I need to make a
      decision before it is too late for a safe operation to be conducted. Salam
Praise be to Allah.Yes, there are benefits of circumcision insofar as it is part of the sunan
    (ways) of the Prophets and is part of the sunan al-fitrah (acts that befit the
    natural state of man). It is cleaner and healthier in terms of urination and intercourse,
    and prevents infection, etc. These and other benefits far outweigh the pain caused, which
    is less for infants than for adults. 
Moreover, a number of the scholars have said that circumcision is
    obligatory for males. Ibn Qudaamah (may Allaah have mercy on him) said in his book al-Mughni:
    Circumcision is an obligation for men and an honour, not an obligation, for
    women. This is the opinion of a number of scholars. Ahmad said: It is more of
    an obligation for men, because if a man is not circumcised, this piece of skin will be
    dangling down over the head of the penis and it will be too difficult to clean left-over
    urine properly. It is not so strict in the case of women. Abu Abd-Allaah said:
    Ibn Abbaas used to be very strict in this matter, and it is reported that he
    said that no Hajj or salaah would be accepted, i.e., from the one who is not
    circumcised. Al-Hasan was more lenient; he said: If a person enters Islam, it
    is not essential for him to be circumcised. And he said: Black and white
    people embraced Islam, but not one of them was checked or forced to get circumcised.
The evidence that it is obligatory is the fact that covering the awrah
    (private parts) is obligatory, so if circumcision were not obligatory, it would not be
    permissible for the one who wants to be circumcised to uncover his awrah for
    this purpose. Circumcision is one of the signs of a Muslim, and like the other signs, it
    is obligatory. If an adult male embraces Islam and is afraid that circumcision would be
    harmful for him, then he is excused, because a person may be excused from ghusl,
    wudoo, etc., if he fears that they may be harmful for him, so it is more so in the
    case of circumcision. If a person is confident that it will not be harmful, then he has to
    do it. Hanbal said: I asked Abu Abd-Allaah about the Dhimmi (non-Muslim under
    Islamic rule) who embraces Islam: did he think that he should be circumcised? He said:
    There is no alternative to that (i.e. he has to). I asked: what if he or she
    is advanced in age? He said: It is better for him to be circumcised, because of the
    hadeeth: Ibraaheem was circumcised when he was eighty years old, and Allaah
    says (interpretation of the meaning):  it is the religion of your father
    Ibraaheem [al-Hajj 22:78]
So our advice to you is to go ahead and have your son circumcised by
    someone who is skilled and experienced. The Prophet 
 (peace and blessings of Allaah be
    upon him) said: Five things are part of the fitrah: circumcision, removing
    the pubic hair, trimming the moustache, cutting the nails, and plucking the armpit
    hair. (Reported by al-Bukhaari, 5441)
May Allaah help us and you to do good.