Bukhari

Hadith Commentary:
In the explanation of this hadith, Hafiz Ibn Hajar states:
And likewise, Ibrahim al-Harbi has narrated it in his book *Gharib al-Hadith* from Jabir, who said: The Messenger of Allah (sallallahu alayhi wa sallam) campaigned against the tribe of Muharib Khasafah at Nakhl. The Muslims were seen in a state of heedlessness, so a man from among them, named Ghawrath ibn al-Harith, came until he stood over the Messenger of Allah (sallallahu alayhi wa sallam) with a sword. He mentioned the incident, and in it is: The Bedouin said, “Except that I pledge to you that I will not fight you, nor will I be with a people who fight you.” So he let him go free. He then went to his companions and said, “I have come to you from the best of people.”
Al-Waqidi has mentioned in a similar account of this story that he (Ghawrath) accepted Islam, and that he returned to his people, and through him, many people were guided.
(*Fath al-Bari*)
In summary, the Noble Messenger (sallallahu alayhi wa sallam) waged jihad against the tribe named Khasafah in a region of date palms, and on the return, the Muslims, in the afternoon, dispersed and lay down to rest under various trees.
At that time, a man from this tribe, named Ghawrath ibn al-Harith, came with a drawn sword and stood over the head of the Noble Messenger (sallallahu alayhi wa sallam).
Thus, this entire incident took place, and in it is also that later, when that Bedouin failed in his attempt, he said, “I make a pact with you to refrain from fighting, and also that I will not support any people who fight you.”
The Prophet (sallallahu alayhi wa sallam) let him go, and he went back to his companions and said to them, “I have come from the presence of such a noble person, who is the best kind of man.”
Al-Waqidi has also mentioned in a similar story that later this man accepted Islam, returned to his people, and through him, many creatures were guided.

Hadith Commentary:
➊
Najd refers to elevated land, while low-lying land is called Ghawr or Tihamah, and the region of Dhat al-Riqa‘ is also in Najd. Thus, by the expedition of Najd, what is meant is the expedition of Dhat al-Riqa‘.
Abu Hurayrah (radi Allahu anhu) performed the prayer of fear (salat al-khawf) in the expedition of Najd, that is, the expedition of Dhat al-Riqa‘, and Abu Hurayrah (radi Allahu anhu) became Muslim and presented himself in the service of the Messenger of Allah (sallallahu alayhi wa sallam) during the days of the siege of Khaybar.

➋
From this hadith, Imam al-Bukhari (rahimahullah) established that the expedition of Dhat al-Riqa‘ occurred after the expedition of Khaybar, because Abu Hurayrah became Muslim during the days of Khaybar.
Then, after embracing Islam, he performed the prayer of fear (salat al-khawf) with the Messenger of Allah (sallallahu alayhi wa sallam) in the expedition of Dhat al-Riqa‘.
In the narration of Abu Dawud, there is detail that Marwan ibn al-Hakam asked Abu Hurayrah (radi Allahu anhu):
“Did you perform the prayer of fear (salat al-khawf) with the Messenger of Allah (sallallahu alayhi wa sallam)?” Abu Hurayrah replied:
“Yes, I did.”
Marwan said:
“When did you perform it?”
Abu Hurayrah said:
“During the expedition of Najd, at the time of jihad.”
(Sunan Abi Dawud, Salat al-Safar, Hadith: 1240 and Fath al-Bari: 7/535)

➌
It should be clear that regarding the prayer of fear (salat al-khawf), various forms are mentioned in the books of hadith. Depending on the circumstances and location, whichever form is suitable should be acted upon, and this is subject to the discretion of the leader of the time.
And Allah knows best.

Important Note:
On the occasion of the Battle of the Trench (Ghazwah al-Khandaq), Allah, the Exalted, granted the Muslims victory and success.
In this way, the authority of the Muslims in Madinah Tayyibah became strong, and after the Battle of Uhud, the surrounding Bedouins had created chaos and entangled the Muslims in severe difficulties. They would attack the callers to Islam in a most cruel manner and put them to death. Now their audacity had increased to such an extent that they were contemplating an assault on Madinah Tayyibah.
During those days, the Messenger of Allah (sallallahu alayhi wa sallam) received information that two tribes of Banu Ghatafan—Banu Muharib and Banu Tha‘labah—were gathering manpower from the Bedouins and villagers for battle.
Upon receiving this news, he (sallallahu alayhi wa sallam) decided to launch a raid on Najd, the purpose of which was to instill fear in these hard-hearted Bedouins so that they would not dare to carry out such severe actions against the Muslims again.
When he launched the raid, the Bedouins, overcome by fear, fled.
The scholars of biography (ahl al-siyar) have mentioned a specific expedition in this regard that took place in the land of Najd, and they consider this very expedition to be the expedition of Dhat al-Riqa‘.
Its purpose was to deliver a decisive blow to the power of the Bedouins so that they would not dare to turn towards Madinah again.
Imam al-Bukhari (rahimahullah), under the aforementioned heading, has narrated hadiths related to this very expedition.
And Allah knows best.