Praise be to Allah.
Marriage is a shar‘i contract between a man and woman, by means of which she becomes permissible for him. As for marriage between a man and another man, or between a woman and another woman, that is not a marriage. Rather it is one of the worst and most abhorrent of immoral and shameful deeds. It is not permissible for a Muslim who believes in Allah and the Last Day to do that. {Indeed, it was an immorality and hateful [to Allah] and was evil as a way} [an-Nisa’ 4:22]. Please see also the answer to question no. 38622 .
The marriage contract is a contract which Allah has caused to be of great significance and high status, and He called it {a solemn covenant} [an-Nisa’ 4:21]. So it is not permissible to treat it lightly or make it something to toy with under any circumstances.
Undoubtedly the same-sex marriage – even if it is a pretence – is a kind of treating this solemn covenant lightly, and it is a kind of approval of this type of invalid marriage, which the Muslim should be too disgusted to even mention, let alone think about doing it.
If this sham marriage is with a woman who is permissible for you to marry, it is not permissible for you to go ahead with it, so how about if it is with a man who is of the same gender as you?!
In Fatawa al-Lajnah ad-Da’imah (18/98) it says: The marriage contract is one of the contracts which Allah has ordained should be of great significance, and He called it {a solemn covenant} [an-Nisa’ 4:21]. Therefore it is not permissible to fake a marriage contract for the purpose of obtaining a residence permit. End quote.
They were asked about the ruling on doing a sham marriage contract in order to obtain nationality, and the answer was: This marriage contract is not permissible, because it is lying and deceit… End quote. Fatawa al-Lajnah ad-Da’imah (18/448).
Conclusion: it is not permissible for you to do this marriage contract, whether that is in earnest or in jest, in a real sense or as a pretence. A permissible aim does not justify prohibited means, let alone doing that by way of cheating, deceit, lying and using tricks that are Islamically unacceptable.
Please see also the answer to question no. 103432 .
And Allah knows best.
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