2153 — Mūsā ibn Ismāʿīl narrated to us, Ḥammād narrated to us, from Suhayl ibn Abī Ṣāliḥ, from his father, from Abū Hurayrah, that the Prophet ﷺ said: "Every son of Adam has his share of fornication" — with this story — he said: "And the two hands commit fornication, and their fornication is the grasping; and the two legs commit fornication, and their fornication is the walking; and the mouth commits fornication, and its fornication is the kissing."

2154 — Qutaybah ibn Saʿīd narrated to us, al-Layth narrated to us, from Ibn ʿAjlān, from al-Qaʿqāʿ ibn Ḥakīm, from Abū Ṣāliḥ, from Abū Hurayrah, from the Prophet ﷺ — with this story — he said: "And the ear, its fornication is the listening."

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And his saying: "It is more akin to the minor lapses (al-lamam)." Al-Khaṭṭābī said: By this he means what Allah has pardoned of minor sins, and it is the meaning of His saying, the Exalted: {Those who avoid the major sins and immoralities, except minor lapses} [al-Najm: 32] — that is, the minor sins that a person commits intermittently, from which scarcely anyone is safe except one whom Allah protects and preserves. The look and the speech are only called fornication because they are precursors to fornication, for the eye is a scout, the tongue is a suitor, and the private part is what confirms fornication and actualizes it by deed.

Ibn Baṭṭāl said: Allah has graciously favored His servants by forgiving minor lapses when the private part does not confirm them; but when the private part confirms them, that is a major sin.

(1) Its chain of transmission is authentic. Ḥammād: he is Ibn Salamah al-Baṣrī, and Abū Ṣāliḥ: he is Dhakwān al-Sammān.
Muslim (2657) also narrated it via the path of Wahb ibn Khālid, from Suhayl ibn Abī Ṣāliḥ, with it, and he said: "And the tongue, its fornication is speech" instead of: "And the mouth commits fornication, and its fornication is the kissing."
It is also in the Musnad of Aḥmad (8526) and (10920).
See what precedes and follows it.

(2) An authentic ḥadīth, and this is a strong chain of transmission on account of Ibn ʿAjlān — who is Muḥammad al-Qurashī. Al-Layth: he is Ibn Saʿd.
Muslim (2657) also narrated it via the path of Suhayl ibn Abī Ṣāliḥ, from his father, with it.
It is also in the Musnad of Aḥmad (8932), and Ṣaḥīḥ Ibn Ḥibbān (4423).
See its two predecessors.