Bukhari

Hadith Commentary:
➊
In this surah, regarding Dawud (alayhis salam), Allah the Exalted says:
"And he realized that We had tested him, so he sought forgiveness from his Lord and fell down in prostration and turned in repentance."
(: Sad: 24)
By "fell down in humility" is meant that he performed prostration (sajdah).
When he performed prostration at this point, the Messenger of Allah (sallallahu alayhi wa sallam) also performed prostration in following him; therefore, we too should perform prostration.

➋
Ibn Abbas (radi Allahu anhu) said:
The prostration of Surah Sad is not among the emphasized prostrations, but I saw the Messenger of Allah (sallallahu alayhi wa sallam) perform this prostration.
(Sahih al-Bukhari, Sujud al-Qur’an, Hadith: 1069)

Hadith Commentary:
Although this hadith is not directly related to this chapter, Surah Sad contains the account of Dawud (alayhis salam), and in it, the prostration (sajdah) is also in gratitude for the acceptance of Dawud’s repentance. Due to this relevance, it has been mentioned here.

Hadith Commentary:
➊
Since Surah Sad contains the account of Dawud (alayhis salam) and his prostration, this hadith has been mentioned here due to that relevance.

➋
The meaning of “Azā’im as-Sujūd” is that it is not among the emphasized prostrations, i.e., the prostration of Surah Sad is not obligatory but rather a prostration of gratitude (sajdah shukr).
It is narrated from Abu Sa’id al-Khudri (radi Allahu anhu) that the Messenger of Allah (sallallahu alayhi wa sallam) recited Surah Sad on the pulpit. When he reached the verse of prostration, he descended and performed prostration. Then, on another day, he recited it again, and when he reached the verse of prostration, the people prepared themselves for prostration. He (sallallahu alayhi wa sallam) said:
“This was due to the repentance of a prophet, but I have seen you preparing for prostration.” Then he descended and performed prostration.
(Sunan Abi Dawud, Kitab as-Sujud, Hadith: 1410)

➌
From this narration, it is understood that the prostration of Surah Sad is not among the emphasized prostrations.
And Allah knows best.

Hadith Commentary:
It is narrated in al-Nasa’i that the Noble Prophet (sallallahu alayhi wa sallam) performed prostration (sajdah) in Surah Sad and said: “This prostration was done by Dawud (alayhis salam) as repentance, and we perform this prostration as an act of gratitude.” In this hadith, the phrase “not among the obligatory prostrations (lays min ‘azā’im al-sujūd)” also means that the prostration was originally that of Dawud (alayhis salam), and we too, following his sunnah, perform this prostration out of gratitude.

Allah Ta’ala accepted the repentance of Dawud (alayhis salam).

And what is meant by “azā’im” are those (prostrations) for which a command in the imperative form has been explicitly stated, such as the imperative verb, etc.
(Fath al-Bari)

That is, by “azā’im” is meant those for which emphasis has been conveyed with the imperative form.

The prostration in Surah Sad is not of this type; however, as an act of gratitude, it is certainly a sunnah.

Hadith Commentary:
By "Azā'im Sujūd" are meant those prostrations of recitation (sujūd al-tilāwah) which have been emphatically enjoined to be performed.

It is narrated from Ali (radi Allahu anhu) that the prostrations in Sūrah Ḥā Mīm Sajdah, al-Najm, Iqra’, and alif-lām-mīm Tanzīl are among the Azā'im Sujūd.
(al-Sunan al-Kubrā by al-Bayhaqī: 2/315, and al-Muṣannaf by Ibn Abī Shaybah: 1/378, no. 4349)

Regarding the prostration in Sūrah Ṣād, Ibn ‘Abbās (radi Allahu anhu) states that this prostration is not among the Azā'im Sujūd.

In one narration, it is mentioned that among the prophets whom the Messenger of Allah (sallallahu alayhi wa sallam) was commanded to follow is Dāwūd (alayhis salam). Since he performed a prostration, therefore, a prostration should be performed in Sūrah Ṣād.
(Ṣaḥīḥ al-Bukhārī, Ḥadīth of the Prophets, ḥadīth: 3421)

In Sunan al-Nasā’ī, it is reported that the Messenger of Allah (sallallahu alayhi wa sallam) said regarding the prostration of Ṣād:
“This prostration of Dāwūd (alayhis salam) was as repentance, and we perform the prostration in his following as gratitude.”
(Sunan al-Nasā’ī, al-Iftitāḥ, ḥadīth: 958)

In Abū Dāwūd, it is narrated that the Messenger of Allah (sallallahu alayhi wa sallam) recited Sūrah Ṣād on the pulpit. When he reached the place of prostration, he descended and performed the prostration, and the people also performed the prostration with him. Then, on another day, he recited it, and the people prepared for prostration as before, so he said:
“This prostration was due to the repentance of a prophet, but I have seen that you have already prepared for prostration.”
Therefore, he descended from the pulpit and performed the prostration.
(Sunan Abī Dāwūd, Sujūd al-Qur’ān, ḥadīth: 1410)

The people also performed the prostration with him.

From this narration, it is understood that there is a prostration in this (verse), but there is no emphasis regarding it.
(Fatḥ al-Bārī: 2/714)

Commentary: 1 ؎:
This refers to the Prophet Dawud (alayhis salam).

958. Commentary:

➊ In the Noble Qur’an, there are certain verses in which the obedience of Allah’s righteous servants and their prostration (sujud) is mentioned, or in which arrogance is condemned, or humility, servitude, and prostration before Allah are praised, or in which the command to prostrate is given. When a believer recites these verses, he spontaneously falls into prostration. These are called the verses of prostration (ayat al-sujud), and this prostration is called the prostration of recitation (sajdat al-tilawah). If the reciter is able to perform the prostration, he should do so and not let the opportunity pass. If he is not in a position to prostrate, he should lower his head and indicate the prostration, for example: someone riding a bicycle or driving a vehicle. If it is possible to get down and perform the prostration, that is best. If someone is reciting and is able to prostrate, he should also do so. The prostration of recitation (sajdat al-tilawah) is recommended (mustahabb), and it is best not to omit it. For detailed rulings and issues regarding the prostration of recitation, see: [سنن ابوداود اردو سجود القرآن ، كا ابتدائيه ، طبع دارالسلام ، و ذخيرة العقبي شرح سنن النسائي : 196-190/12]

➋ The prostration in Surah Sad is not accepted by Imam al-Shafi‘i rahimahullah because the word “prostration” (sujud) itself does not appear in the verse; rather, the words are: «﴿خَرَّ رَاكِعًا وَأَنَابَ﴾» [ص : 24 : 38] whereas other scholars affirm this prostration because the meaning is that of prostration, even if the wording is « رَاكِعًا ». Imam Malik is also in agreement with Imam al-Shafi‘i.

➌ Prophet Dawud (David) alayhis salam made an (ijtihadi) error, the details of which are not mentioned in the Noble Qur’an or in authentic hadith, so we should not delve into it. When he realized his mistake, he prostrated in repentance. Allah accepted his repentance, so we prostrate in gratitude for that.

Takhrij:
«أخرجه البخاري، سجود القرآن، باب سجدة ص ، حديث:1069.»©Explanation:
➊ From this it is understood that in Surah Sad, the Prophet (sallallahu alayhi wa sallam) performed prostration (sajdah); however, he did not command it nor did he emphasize it.
➋ From this it is understood that some actions, although they are Sunnah, are not emphasized. They too fall under the category of the Sunnah of the Best of Mankind (sallallahu alayhi wa sallam).

Benefit:
From this hadith, it is understood that the prostration of recitation (sajdah tilawah) in Surah Sad is not obligatory; if someone wishes to perform it, they may do so, and if someone does not perform the prostration, there is no sin upon them. The "determined prostrations" (azaa'im as-sujood) refer to those prostrations of recitation for which performance has been emphasized.