the secret behind prohibiting the marriage of a muslim woman from a non-muslim man .
why does islam allow a muslim man to get married to al-ketabeyyat (christian or jewish women) while prohibiting a muslim woman to do the same?
this is a good and logical question , and before replying to it we have to confirm that islam prohibited this :
and do not marry female associators (those who associate others with allah) until they believe; and indeed a believing bondwoman is more charitable than a female associator, even if you may admire her. and do not (allow) associators to marry (your females) until they believe. and indeed a believing bondman is more charitable than an associator, even if you may admire him.(al-baqara:221)
this prohibition is mainly due to the fact that a woman, usually, follows her husband, for the man has a greater influence on his wife than she has on him. in fact, islam has a number of aims of which are the following two:
the first: islam aims at being apprehended clearly and unequivocally. this results in people's faith that it is the religion of truth. that is why islam granted a muslim man the right to get married to a non-muslim woman providing that she is one of the people of the book, which means her being christian or jewish, because she, at least, believes in allah the almighty and his inspiration, regardless of the nature of this belief. accordingly, she can understand islam easier. especially when she gets married to a true muslim committed to islam's doctrines in all his sayings and deeds. for when she touches in him islam's ethics along with his handsome equitable behavior towards her, this can be a reason for her to convert to islam. however, she has the right to stick to her religion and no one has the right to force her to convert "there is no compulsion in the religion" (al-baqara:256).
the second: islam aims at keeping its followers committed and connected to it. therefore, it doesn't let them being exposed to whatever has a negative effect on their faith. this is called temptation in religion "and temptation in religion is greater than killing"(al-baqara:217).
in fact, this kind of temptation takes several shapes and of which might be tormenting the muslim to change his/her believes.(in this case: being married to a non-muslim whatever his religion is).and why is that considered a temptation in religion? simply because, as stated above, the husband has the greater influence on his wife, and perhaps this non-muslim husband tries to exert a negative influence on his muslim wife leading her to leave her religion or, at least, to be uncommitted to its holly doctrines, which isn't wanted by islam in what concerns its followers. for islam wants to provide the suitable atmosphere for them to be committed to its teachings.
this is why islam urged the muslim woman to choose a good husband. even when she is getting married to a muslim man, she has to select the one who follows islam's doctrines commitedly and rejects who ignores them. all of that is for a muslim woman to cling to her religion and transcends herself from every negative influence.