Bukhari

Hadith Commentary:
(1)
From this hadith, it is understood that tranquility (tuma’ninah) during prostration (sujud) is necessary.
In one narration, it is stated that if you die in this state, you will die contrary to the natural disposition (fitrah) upon which Allah, the Exalted, sent Muhammad (sallallahu alayhi wa sallam).
(Sahih al-Bukhari, al-Adhan, Hadith: 791)
It should be noted that this very chapter (26), including the mentioned hadith, has already passed previously.
However, earlier Imam al-Bukhari (rahimahullah) mentioned it for a different purpose.
For details, it is necessary to refer back to the mentioned hadith. Also, this hadith has already been stated earlier (791), but there, the narrator from Hudhayfah (radi Allahu anhu) was Zayd ibn Wahb al-Juhani, who set out from his home to visit the Messenger of Allah (sallallahu alayhi wa sallam), but while he was still on the way, the Messenger of Allah (sallallahu alayhi wa sallam) passed away. In this place, however, the narrator from Hudhayfah (radi Allahu anhu) is Abu Wa’il Shaqiq.
(‘Umdat al-Qari: 4/554, 521)
(2)
It should be noted that the Messenger of Allah (sallallahu alayhi wa sallam) commanded a person who did not perform his bowing (ruku‘) and prostration (sujud) properly to repeat his prayer, as has been detailed in the hadith of the one who performed his prayer badly (hadith al-musi’ salah).
(Sahih al-Bukhari, al-Adhan, Hadith: 793)

Hadith Commentary:

That is, your end (may Allah protect us) will be upon disbelief.

Those who oppose the Sunnah of the Messenger of Allah (sallallahu alayhi wa sallam) should fear such an evil end.

SubhanAllah, the life and death of the Ahl al-Hadith are both good.

After death, there will be no shame before the Messenger of Allah (sallallahu alayhi wa sallam).

They continued to follow his hadith as long as they lived, and their end was also upon hadith.

(Maulana Waheed al-Zaman rahimahullah)

Hadith Commentary:
(1)
In one narration, it is mentioned that Hudhayfah (radi Allahu anhu) asked him: "For how long have you been praying in this manner?" He replied, "For forty years I have been praying like this." (Fath al-Bari: 2/256)
From this hadith, it is understood that bowing (ruku) and prostration (sujud) in prayer should be performed with calmness and tranquility.
Doing so is obligatory.
Negligence in this matter is tantamount to ruining one's prayer.

(2)
Some individuals say that the essence of ruku is to bow, and the essence of sujud is to place the forehead on the ground; if someone suffices with only this, then his prayer is valid.
However, this position is contrary to the ahadith, because in the ahadith there is great emphasis on the moderation (ta'dil al-arkan) of the pillars.
Ta'dil al-arkan is that the body reaches its natural posture and the movement of transition turns into stillness and tranquility.

(3)
Hudhayfah (radi Allahu anhu) said regarding the one who performed incomplete ruku and sujud:
"You have not prayed," just as the Messenger of Allah (sallallahu alayhi wa sallam) said to the one who spoiled his prayer by performing it contrary to the Sunnah method:
"Go, repeat the prayer, you have not prayed." (Fath al-Bari: 2/256)

(4)
These ahadith necessitate that moderation and tranquility are essential; without them, the obligation (fard) will not be fulfilled.