922 — Aḥmad ibn Ḥanbal and Musaddad narrated to us — and this is his wording — he said: Bishr — meaning Ibn al-Mufaḍḍal — narrated to us, Burd narrated to us, from al-Zuhrī, from ʿUrwah ibn al-Zubayr, from ʿĀʾishah, who said: The Messenger of Allah — peace be upon him — Aḥmad said: was praying — and the door was closed upon him. I came and asked for the door to be opened — Aḥmad said: so he walked — and opened it for me, then returned to his place of prayer. And he mentioned that the door was in the qiblah (direction of prayer). (1)

169 — Chapter: Returning the greeting of salām during prayer

923 — Muḥammad ibn ʿAbd Allāh ibn Numayr narrated to us, Ibn Fuḍayl narrated to us, from al-Aʿmash, from Ibrāhīm, from ʿAlqamah, from ʿAbd Allāh, who said: We used to greet the Messenger of Allah — peace be upon him — while he was in prayer, and he would return the greeting to us. But when we returned from the presence of the Negus, we greeted him and he did not return the greeting to us, and he said: "Indeed, in prayer there is occupation (with it)." (2)

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And al-Khaṭṭābī said in "Maʿālim al-Sunan": In this there is evidence for the permissibility of slight action in prayer, and that the continuity of action twice in one instance does not invalidate the prayer. For the killing of the snake is usually done with one blow or two blows. But if the action becomes continuous and reaches the limit of being excessive, the prayer is invalidated.

We say: And Shaykh al-Islām al-Sarakhsī held the view that it does not invalidate his prayer, because this is an action that was permitted for the one praying, so it resembles walking after passing wind, drawing water from a well, and performing ablution.

(1) Its chain of transmission is authentic. Burd: he is Ibn Sinān al-Dimashqī.
It was also recorded by al-Tirmidhī (607) and al-Nasāʾī in "al-Kubrā" (528) via the path of Burd ibn Sinān, with this chain. Al-Tirmidhī said: A ḥasan gharīb ḥadīth.
It is in "Musnad Aḥmad" (24027) and "Ṣaḥīḥ Ibn Ḥibbān" (2355).
In the narration of al-Nasāʾī and Ibn Ḥibbān: that he — peace be upon him — was praying a voluntary prayer. Al-Tirmidhī included it under the chapter: What is permissible of walking and action in voluntary prayer.

(2) Its chain of transmission is authentic. Ibn Fuḍayl: he is Muḥammad, and al-Aʿmash: he is Sulaymān ibn Mihrān, and Ibrāhīm: he is Ibn Yazīd al-Nakhaʿī, and ʿAlqamah: he is Ibn Qays al-Nakhaʿī, and ʿAbd Allāh: he is Ibn Masʿūd.