It depends on what kind of a non-muslim they are.
If it is a Hindu, then polygyny [marrying many women] is not uncommon and in fact, their scriptures are full of examples – Rama’s father had atleast four wives. I tried to find the Sanskrit phrase that said: ‘a king is allowed/has a hundred wives,’ as explained by a teacher in school. Krishna, their blue god (in text it is dark/black, but in comics we always found him blue much to our amusement) married hundred women and so forth.
Polyandry [one woman marrying many men] is not uncommon either – Draupadi married all the five brothers, the Pandavas. [from the Mahabharata]. Polyandry is also found in many cultures – the Arabs in jahiliyyah ‘shared’ women. There is a famous and raunchy story about Imru’u al-Qays deceiving two brothers by putting his stick out of the hut…
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If it is a person from those whom we term ‘people of the book’, it is clearly mentioned about the prophets Dawūd and Sulaymān, álayhimu’s salām that they married more than hundred wives. There are also other examples in the earlier books. Only that the Jews don’t consider them as prophets – only kings.
Also, the Christians consider sex as a dirty thing and hence it somehow diminishes a person’s piety if they marry and have sex. Whereas we don’t – we consider it to be a healthy thing and there is a legal way to channel those desires by getting married. Certainly like the Jews and Christians, illegal ways to seek/attain those pleasures are forbidden and carry punishments both here and in the hereafter. But that is a different discussion.
In fact, we believe that Sayyiduna Ýīsā álayhi’s salām will marry when he returns in the final times.
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If it is an agnostic/atheist [or some of the so-called humanists], well it is difficult to argue with them. There are many reasons like culture and context: one cannot reduce everything to conform to values of a particular place and of a different age and talk about everything in terms of a monoculture.
They are obsessed about Western ‘values’ like allowing women to mix freely with men and wish to impose this on the whole world. They will not compromise on whatever they hold dear, so why should we? We, as Muslims have our own values and we believe that they are divinely ordained. In our value system, it is allowed and that is the end of the story. I ask, why should we play with their rules of the game? If we play, we make the rules.
If you find it offensive, go hang yourself.
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Strictly speaking and personally, I dislike this ‘comparitive religion’ business. There is no point in it. We must be like we are asked to: ‘samiýnā wa aţá-nā’ / we hear and obey. Don’t be fooled by the so-called rationalist arguments; there is no need to conform to their beliefs or value system. These are matters of culture etc., which are specific to each shariáh or canon-law. For example, prostrating to others in veneration was allowed for the previous prophets [and in egypt], but disallowed in ours. Similarly, some marriages allowed in earlier shariáh are disallowed in ours.
As I said, these are cultural matters and cannot be imposed on anyone even when religion is not involved. Let them talk about values that are universal – like mercy, truthfulness, helping others, kindness etc. Comparing apples and oranges, only the bananas seem more worthy.
Allāh táālā says: ‘Whosoever wishes to have faith, then let them be believers; and whosoever wants to disbelieve, then let them remain infidels’ [Al-Kahf]
Allāh táālā knows best.
