Answer
1 ابْنِ أَبِي عُمَیر عَن بَعْض أَصْحَابِنَا عَن أَبِي عَبْداللَّه فِي رَجُلٍ يَعْبَثُ بِالْغُلَامِ قَالَ إِذَا أَوْقَبَ حَرُمَتْ عَلَيْهِ ابْنَتُهُ و أُخْتُهُ
📚 Al-Kafi, vol. 5, p. 417
Imam Sadiq (peace be upon him) said about a man who plays with a young boy: If he penetrates, (marriage with) his (the penetrated person's) daughter and sister becomes forbidden for him (the penetrator)!
2 حماد بنِ عثمان قال: قُلْتُ لِأَبِي عَبْداللَّه رَجُلٌ أَتَى غُلَاماً أَ تَحِلُّ لَهُ أُخْتُهُ قَالَ فَقَال إِنْ كَانَ ثَقَبَ فَلَا
📚 Al-Kafi, vol. 5, p. 417
Hammad ibn Uthman said: I said to Imam Sadiq (peace be upon him): A man goes to a young boy, is (marriage with) his sister permissible for him? He said: If he penetrates (in the anus), then no!
3 روی عن أَبِي عَبْداللَّه في رَجُلٍ لَعِبَ بِغُلَامٍ قال إِذَا أَوْقَبَ لَمْ تَحِلَّ لَهُ أُخْتُهُ أَبَداً
📚 Uqab al-Amal, p. 316
Imam Sadiq (peace be upon him) said about a man who plays with a young boy: If he penetrates, his sister is not permissible for him forever!
4 عن أَبِي عَبْداللَّه فِي رَجُلٍ لَعِبَ بِغُلَامٍ هَلْ تَحِلُّ لَهُ أُمُّهُ قَالَ إِنْ كَانَ ثَقَبَ فَلَا
📚 Tahdheeb, vol. 7, p. 310
Imam Sadiq (peace be upon him) was asked about a man who plays with a young boy, is marriage with his mother permissible for (the penetrator)? He said: If he penetrates, then no!
5 ابن أَبِی عُمَیْر عَنْ بَعْضِ أَصْحَابِه عن أَبِي عَبْداللَّه فِي رَجُلٍ يَأْتِي أَخَا امْرَأَتِهِ فَقَالَ إِذَا أَوْقَبَهُ فَقَدْ حَرُمَتْ عَلَيْهِ الْمَرْأَةُ
📚 Al-Kafi, vol. 5, p. 418
Imam Sadiq (peace be upon him) said about a man who has relations with his wife's brother: If he penetrates him, his wife becomes forbidden to him!
6 موسى بن سعدان عن بعض رجاله قَالَ: كُنْتُ عِنْد أَبِي عَبْداللَّه فَقَالَ لَهُ رَجُلٌ مَا تَرَى فِي شَابَّيْنِ كَانَا مُضطجعین فَوُلِدَ لِهَذَا غُلَامٌ و لِلْآخَرِ جَارِيَةٌ أَيَتَزَوَّجُ ابْنُ هَذَا ابْنَةَ هَذَا قَالَ فَقَالَ نَعَمْ سُبْحَانَ اللَّهِ لِمَ لَا يَحِلُّ فَقَالَ إِنَّهُ كَانَ صَدِيقاً لَهُ قَالَ فَقَالَ وَ إِنْ كَانَ فَلَا بَأْسَ قَالَ فَإِنَّهُ كَانَ يَفْعَلُ بِهِ قَالَ فَأَعْرَضَ بِوَجْهِهِ ثُمَّ أَجَابَهُ و هُوَ مُسْتَتِرٌ بِذِرَاعِهِ فَقَالَ إِنْ كَانَ الَّذِي كَانَ مِنْهُ دُونَ الْإِيقَابِ فَلَا بَأْسَ أَنْ يَتَزَوَّجَ و إِنْ كَانَ قَدْ أَوْقَبَ فَلَا يَحِلُّ لَهُ أَنْ يَتَزَوَّجَ
📚 Al-Kafi, vol. 5, p. 417
In the above hadith, Imam Sadiq (peace be upon him) was asked about two young men who had sexual relations and later one of them had a son and the other had a daughter, can their children marry each other? The Imam said: If the act between them was less and other than penetration, there is no problem for them to marry, and if he penetrated, it is not permissible for him to marry!
✅ According to the above narrations and others, if, God forbid, a man commits sodomy with a boy by penetrating the anus, the sister, daughter, and mother of that penetrated person become eternally forbidden for the penetrator, and also according to narration 6 , the marriage of the children of two men who had sexual relations with penetration in the past is not permissible with each other.
✅ No specific limit for penetration has been defined in the narrations, and it includes any amount of penetration.
✅ Also, please pay attention to the following narration:
7 زرارة عن أبا جَعْفَرٍ في حديث إِنَّ الْحَرَامَ لَا يُفْسِدُ الْحَلَالَ و لَا يُحَرِّمُهُ
📚 Al-Kafi, vol. 5, p. 416
Imam Baqir (peace be upon him) said in a hadith: Indeed, the forbidden does not corrupt the permissible and does not make it forbidden!
✅ According to the above general principle which is narrated in various narrations and according to the apparent meaning of the mentioned narrations, if the penetration in the anus occurs after the marriage contract, there is no reason for the previous contract to become forbidden and corrupt, and the eternal prohibition of the penetrator's marriage with the daughter and mother of the penetrated person is only if this act occurs before their marriage, but according to narration 5 , if the penetration is with the wife's brother, it makes that woman forbidden to that man even after the contract.
✅ Those who have unknowingly married such women who were eternally forbidden to them, there is no way for them except an immediate separation.
✅ The content of the narrations on this topic is the prohibition of the daughter, sister, and mother of the penetrated person to the penetrator, and the daughter, sister, and mother of the penetrator are not forbidden to the penetrated person.
✅ It is obvious that in the absence of penetration, the prohibition of marriage is not established, but its severe abhorrence remains in its place.
✅ Discussions have been raised about the maturity and immaturity of the parties to sodomy, but due to the recommendation of the Ahl al-Bayt (peace be upon them) for caution, especially in the matter of marriage, it is necessary to avoid marriage in all cases.