879 – Ibn ʿAbbās (may Allah be pleased with him) reported: “The Messenger of Allah (peace and blessings be upon him) said, ‘Allah will not look at a man who goes to a man, or to a woman, through her rear passage.’” Narrated by al-Tirmidhī, al-Nasāʾī, and Ibn Ḥibbān, and it has been critiqued as being mawqūf (1).

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Hadith grade:
The hadith is sound (ḥasan).
This exact wording has come through numerous chains from a group of Companions, among them ʿUmar, ʿAlī, Ibn Masʿūd, Jābir, Ibn ʿAbbās, Ibn ʿUmar, al-Barāʾ, Anas, Abū Dharr, ʿUqbah ibn ʿĀmir, ʿAlī ibn Ūlqah, and Tulq ibn ʿAlī.
Each chain has some point of discussion, yet by their sheer number and variety they strengthen one another, so the hadith is ḥasan—indeed, even ṣaḥīḥ—and Ibn Ḥazm used it as proof.

Points derived from the two hadiths:
1 – The two hadiths show that anal intercourse with women is forbidden. The entire Muslim community has held this view, based on Allah’s words, “So approach them from where Allah has commanded you” [al-Baqarah 2:222], on the strength of these two widely transmitted hadiths, and because the default ruling for private parts is prohibition except where Allah has expressly allowed.

2 – Enjoyment of any part of the wife’s body other than the rear passage is permissible. In the two Ṣaḥīḥs, ʿĀʾishah said: “The Messenger of Allah (peace and blessings be upon him) would tell me to wrap a waist-cloth around myself, and then he would fondle me while I was menstruating.” His instruction to ʿĀʾishah to cover herself when fondling her during her period was to avoid direct contact with the private area.