Bukhari

Hadith Commentary:
The relevance of this hadith to the chapter heading is difficult to ascertain.
Some have said that this is actually a fragment of the previous hadith, and for this reason it has been mentioned here.
It is understood from this that upon returning from a journey, it is Sunnah to enter the mosque and offer two units (rak‘ahs) of voluntary (nafl) prayer as an expression of gratitude, just as it is customary to invite friends and peers upon returning safely, as has been mentioned.

Hadith Commentary:
1.
Some scholars have objected to Imam Bukhari rahimahullah, saying that this last hadith has no connection with the chapter heading, but rather it corresponds to the previous chapter, and therefore it should have been mentioned there.
According to our inclination, this objection is merely for the sake of objection.
In reality, Imam Bukhari rahimahullah wants to show that when the Messenger of Allah sallallahu alayhi wa sallam returned from the expedition of Tabuk, several incidents occurred during the journey which were narrated by Jabir radi Allahu anhu, for example:
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During the journey, Jabir radi Allahu anhu’s camel became exhausted, so he struck it with a stick and it became swift.
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The Messenger of Allah sallallahu alayhi wa sallam bought it from Jabir radi Allahu anhu so that he could help him under the pretext of purchase.
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Upon reaching Madinah Tayyibah, before going home, the Messenger of Allah sallallahu alayhi wa sallam performed two units (rak‘ahs) in the mosque.
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When Jabir radi Allahu anhu was given the camel, he was instructed to go to the mosque and perform two units (rak‘ahs) of prayer.
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Finally, the Messenger of Allah sallallahu alayhi wa sallam paid the price of the camel, gave some extra silver, and also returned the camel.
These incidents have been narrated individually by different narrators.
Among them, Mu‘adh ‘Anbari has narrated a few incidents concisely, so he mentioned from Jabir radi Allahu anhu that the Messenger of Allah sallallahu alayhi wa sallam bought the camel for two uqiyahs of silver, slaughtered a camel or cow at the place of Asrī to host the companions, instructed Jabir radi Allahu anhu to go to the mosque and perform two units (rak‘ahs) of prayer, and finally paid the price of the camel.
The purpose is to show that upon returning from a journey, it is a Sunnah act to go to the mosque and perform two units (rak‘ahs) of gratitude, just as it is a Prophetic Sunnah to host friends and companions upon returning safely from a journey.
2.
In this regard, the practice of Abdullah ibn ‘Umar radi Allahu anhu is also commendable: in the state of residence, he was accustomed to fasting frequently, but when he returned from a journey, he would refrain from fasting for a few days, thinking that friends and companions would come to meet him and it would be necessary to host them, and it is also necessary that the host eat with the guest. On this basis, he would postpone voluntary fasts for a few days.
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radi Allahu ta‘ala anhu.
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