Although sex could be considered a blessed act between a married couple, Islam does put limits on what couples can and cannot engage in. Modest Muse shares a few examples:
1. A man can approach his wife from any direction.
Your wives are a place of sowing of seed for you, so come to your place of cultivation however you wish and put forth [righteousness] for yourselves. And fear Allah and know that you will meet Him. And give good tidings to the believers. 2:223
This verse says you can approach your wife from any direction you want. At that time there were common believes that if you approach your wife from behind that resulted in children, the kids would have some kind of deformity. The Quran simply busted that myth.
2. Anal sex is strictly, strictly forbidden!!!
Although there is no direct verse related to it but there but this is general consensus among Sunni Muslim that Anal sex between husband and wife is not allowed. It is also mentioned in tafsir of the above verse that sex must happen only where it is supposed to be, not in any other place.
Here are some hadiths that proves it is forbidden
Abu Hurairah, Book of Divination and Omens, Sunan Abu Dawood, 3895.
If anyone [resorts to a diviner and believes in what he says (according) to the version of Musa) or] has intercourse with his wife (according to the agreed version) when she is menstruating, or has intercourse with his wife through her anus, he has nothing to do with what has been sent down to Muhammad. On the day of resurrection, Allah will not look at a man who had intercourse with his wife in her anus”— Narrated by Ibn Abi Shayba, 3/529; narrated and classed as sahih by Sunan al-Tirmidhi, 1165
3. Sex during menstruation is forbidden
And they ask you about menstruation. Say, “It is harm, so keep away from wives during menstruation. And do not approach them until they are pure. And when they have purified themselves, then come to them from where Allah has ordained for you. Indeed, Allah loves those who are constantly repentant and loves those who purify themselves. Al Buqarah 2:222
This clearly say sex or intercourse during menstruation is not allowed. Although a man can still fondle his wife in other ways, as the prophet used to do it. But his wife privates parts are not allowed for the husband.
4. Sex is not allowed during Fasting
It is made lawful for you, in the nights of fast, to have sex with your women. They are a cover for you and you are a cover for them … and do not have sexual intimacy with them while you are staying in mosques for I’tikaf. These are the limits set by Allah, so do not go near them. Thus Allah manifests His signs to the people that they may be God-fearing. 2:187
This says simply any type of sex is not allowed during fasting. This also means slight touching for satisfaction purposes is also not allowed as it may lead to more and can be cause of a sin. Older people might have relaxed restriction as their desires are not that strong. This verse was revealed to allow sex during the nights in Ramadan. Because before that sex in the whole month of Ramadan was not allowed. But one sahabi made a mistake and that’s when this verse was revealed to change the rule.
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