SO why do Muslims fast during Ramadan? I have asked Muslims this question many times. They often just answer with a good0natured shrug and "haek biddu Allah," which is a very colloquial way of saying, "That's what Allah wants."
I think about this question of fasting and dietary regulation every Friday when we abstain from anything with warm blood in it: pork, chicken, beef, lamb. Why do we do this? Because Friday is a special day. It is the day when Jesus was crucified, which means that we can honor life in a special way by what we refrain from eating. Now this is not a particularly example of dietary devotion, but I offer it as one reason for such a an exercise of piety.
Islam Q & A in its customary way offered a long rambling answer to this question, in a way that only an imam or Anglican bishop could. Rather than post his prolix answer I will summarize and abridge the four points he has outlined:
a) We Muslims fast the month of Ramadaan because Allaah has commanded us to do so. Allaah says (interpretation of the meaning):
“ O you who believe! Observing As-Sawm (the fasting) is prescribed for you as it was prescribed for those before you, that you may become Al-Muttaqoon (pious)”
b) It is by His wisdom that Allaah has prescribed a variety of acts of worship, so as to test people with regard to how they will obey all these commands. Will they only choose to do that which suits them, or will they do that which pleases Allaah?
c) The reason why fasting was prescribed, which is taqwa (piety) and submission to Allaah. Taqwa means giving up haraam things, and in general terms includes both doing what is commanded and abstaining from what is forbidden. The Prophet (peace and blessings of Allaah be upon him) said: “Whoever does not give up false speech and acting upon it and offensive speech and behaviour, Allaah has no need of his giving up his food and drink.”
So there you have three reasons for the Muslim to fast: that it is a characteristic of the believer to obey what Allah commands; that Allah tests us in our fasting; and that it builds up our piety.
Another interesting question is why fasting is prescribed during Ramadan specifically. I also asked that question many times and one friend was able to tie it to some event in Muhammad's life, but I don't know the story well enough to relay it, nor do I know of the validity of that story. It is very different to the Lenten fast which is for Catholics and Protestants fairly easy, but whose reason is know to many: it is a preparation for Easter and a time to devote to repentance and confession of our sins. (I should point out here that the Orthodox Lenten fast is very difficult, possibly more so than the Islamic sawm of Ramadan.)
However unsatisfactory the answer of our Muslims friends may be to the Christian's question, he has a much more poignant question to ask of evangelicals in general: Why do you not fast at all?
Let me also point out that it is worthwhile to remember Jesus' own teaching on fasting, and compare this to what Muslims are taught:
“When you fast, do not look somber
as the hypocrites do, for they disfigure their faces to show others
they are fasting. Truly I tell you, they have received their reward in
full. But when you fast, put oil on your head and wash your face, so
that it will not be obvious to others that you are fasting, but only to
your Father, who is unseen; and your Father, who sees what is done in
secret, will reward you."
--Matthew 6:16-18
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