Bukhari

Hadith Commentary:
The profession of the Quraysh was trade, while the people of Madinah were farmers.
When the Muhajirun (Emigrants) arrived in Madinah, they preferred their ancestral profession of trade, and in the pursuit of livelihood, both the Ansar and the Muhajirun would remain engaged in their respective occupations. However, the Ashab al-Suffah were exclusively devoted to the learning of religion.
They had no worldly occupation whatsoever.
Among them, Abu Hurairah radi Allahu anhu was the most enthusiastic, and in fact, so devoted to the sciences of the Qur’an and Hadith that he would often neglect even his own hunger, enduring hunger upon hunger, and only when he would begin to faint would he remember his hunger.
Imam Bukhari rahimahullah has brought this hadith here to show that trade, buying and selling, farming, and indeed all worldly occupations are among the necessities of life.
For these, Islam has presented the best principles and guidance, and has encouraged every possible advancement in this regard. A living proof of this are the Ansar and Muhajirun, who, in the era of the Messenger sallallahu alayhi wa sallam, achieved enviable progress in trade and agriculture, and became an example for the world in commerce, farming, and horticulture.
Abu Hurairah radi Allahu anhu was purely a seeker of religious knowledge and had no attachment to worldly occupations; thus, he became the memorizer of thousands of Prophetic hadiths.
From this hadith, a miracle of the Noble Messenger sallallahu alayhi wa sallam is also established: according to his instructions, Abu Hurairah radi Allahu anhu spread out his cloak at the time of the Prophet’s heart-touching speech, and afterwards, he gathered up the cloak and pressed it to his chest, by which his chest was illuminated, and later he surpassed all others among the memorizers of hadith.
Radi Allahu anhu wa ardah. Ameen.

Hadith Commentary:
(1)
The purpose of this hadith is to show that trade, buying and selling, agriculture, and indeed all worldly occupations are among the necessities of life. Allah, the Exalted, has declared them permissible. The noble Companions (radi Allahu anhum) used to engage in these activities in the presence of the Messenger of Allah (sallallahu alayhi wa sallam). He provided them with the best principles and guidance, and encouraged every possible advancement in this regard. The Ansar and Muhajirun achieved enviable progress to the extent that they became an example for the people of the world in this field.

(2)
It should be noted that the profession of the Quraysh was trade, while most of the people of Madinah were farmers. When the Muhajirun arrived in Madinah al-Tayyibah, they preferred their ancestral profession of trade. The Messenger of Allah (sallallahu alayhi wa sallam) maintained them upon this profession.