Abu Dawud

Hadith Commentary:
Imam Bukhari rahimahullah established from this that the Messenger of Allah sallallahu alayhi wa sallam performed prayer in the mosque even in mud and rain. The very purpose of the chapter is that in such calamities, if people come to the mosque, the imam should lead the prayer with them.

Hadith Commentary:
(1)
Since it was the rainy season, as is explicitly mentioned in the hadith, it is most likely that not all worshippers were able to be present in the mosque. Despite this, the Messenger of Allah (sallallahu alayhi wa sallam) arranged the congregational prayer for those who were present in the mosque. The first part of the chapter heading established by Imam Bukhari (rahimahullah) is also this: that if, due to rain or other valid excuses, all people are not able to come to the mosque, then the imam should arrange the congregational prayer for those who are present in the mosque. And Allah knows best.
(2)
This narration is extremely concise; Imam Bukhari (rahimahullah) has mentioned it in detail at several places. Thus, it is clarified that Abu Salamah asked Abu Sa'id al-Khudri (radi Allahu anhu) about Laylat al-Qadr, so he stated that we were in i'tikaf with the Messenger of Allah (sallallahu alayhi wa sallam) during the month of Ramadan. On the twentieth day of Ramadan, he delivered a sermon and said that Laylat al-Qadr should be sought in the odd nights of the last ten nights of Ramadan. Accordingly, I saw myself in a dream prostrating in water and mud. Abu Sa'id al-Khudri (radi Allahu anhu) says that on the twenty-first night, I saw with my own eyes the Messenger of Allah (sallallahu alayhi wa sallam) and his forehead was soiled with mud. This is a clear indication that in that Ramadan, Laylat al-Qadr was on the twenty-first night of Ramadan. (Sahih al-Bukhari, The Virtue of Laylat al-Qadr, Hadith: 2018)

Hadith Commentary:
It is understood that the Messenger of Allah (sallallahu alayhi wa sallam) did not wipe away the traces of water and mud from his blessed forehead.
This is precisely the basis of Imam Humaydi's (rahimahullah) reasoning.

Hadith Commentary:
Imam Bukhari rahimahullah mentioned the issue and its evidence, but did not make any categorical decision regarding it, because there are several possibilities within this evidence. The appearance of traces of soil on the forehead does not necessarily mean that the Prophet sallallahu alayhi wa sallam did not wipe them off during the prayer, because even after wiping, their effects can remain. It is also possible that, due to forgetfulness, he was unable to wipe them off, or that he intentionally left them in order to confirm his dream, or that he did not feel the traces of mud, or that he did so to demonstrate permissibility.

When such possibilities exist within the evidence, it is no longer suitable for definitive argumentation.
(Fath al-Bari: 2/416)
At most, it can be said that if traces of soil appear on the forehead due to prostration, there is no harm in it.

911. Commentary:
There are four renowned hadith scholars who narrated Sunan Abu Dawud from Imam Abu Dawud. The chains of transmission (isnad) of the scholars of hadith reach to them.
➊ Abu Ali Muhammad bin Ahmad bin Amr al-Lu’lu’i al-Basri.
➋ Abu Bakr bin Muhammad bin Abd al-Razzaq al-Tammar al-Basri, known as Ibn Dasa.
➌ Abu Sa’id Ahmad bin Muhammad bin Ziyad bin Bishr, known as Ibn al-A’rabi.
➍ Abu ‘Isa Ishaq bin Musa bin Sa’id al-Ramli, the scribe of Abu Dawud.
The manuscript of al-Lu’lu’i became famous in the East, and the manuscript of Ibn Dasa became famous in the West. [الحطة فى ذكر الصحاح الستة]
There are occasional differences between these manuscripts.

1096. Commentary: It is necessary for the forehead to touch the ground in prostration (sujud), because the very meaning of sujud is to place the forehead on the ground, except in the case of an excuse, such as: a boil or abscess, pain in the back or head, having undergone eye surgery, or any other thing that prevents the forehead from being placed on the ground.

Benefit:
In Sahih Muslim (2796 / 1167), this hadith is mentioned in detail, in which the Messenger of Allah (sallallahu alayhi wa sallam) said:
“I observed i‘tikaf (spiritual retreat) in search of that night during the first ten days, then I observed i‘tikaf in the middle ten nights, then whenever I came for i‘tikaf, it was said to me that the night is in the last ten nights, so whoever among you wishes to observe i‘tikaf should do so in the last ten nights.”
After that, people observed i‘tikaf with him. From this hadith, it is established that the Sunnah i‘tikaf is in the last ten days of Ramadan. It is also understood that rainwater is pure, and it is permissible to pray in mud out of necessity.