Bukhari

Hadith Commentary:
The purpose of presenting all these ahadith is precisely this: that a Muslim continually faces various kinds of hardships and worries, yet he endures them with patience and does not utter a single word of ingratitude, no matter how severe the difficulty may be. He never abandons patience and gratitude. Through all of this, his sins continue to be forgiven and his ranks continue to be elevated. In essence, all of this is encompassed by the verse:
﴿مَنْ يَعْمَلْ سُوءًا يُجْزَ بِهِ﴾ (: an-Nisa: 123).

Hadith Commentary:
(1)
In this world of color and fragrance, every kind of calamity befalls a Muslim and he is faced with worries. He endures them with a cheerful countenance and does not let a word of complaint escape his lips, nor does he let go of patience and gratitude. In return for this, Allah, the Exalted, forgives his sins and his ranks continue to be elevated. Thus, these hardships become an expiation for sins and a means for the elevation of ranks.

(2)
It is mentioned in the hadith that when Allah, the Exalted, determines a certain rank for His servant which he cannot attain through his deeds, then Allah afflicts him with some illness, distress, or financial loss. The servant, by exercising patience over this, attains that rank.
(Musnad Ahmad: 5/272)

Hadith Authentication:
[وأخرجه البخاري 5645، من حديث مالك به]

Jurisprudential Explanation:
➊ It is narrated from Sayyidah Aisha radi Allahu anha that the Messenger of Allah sallallahu alayhi wa sallam said: “No affliction befalls a Muslim, even to the extent of a thorn that pricks him, except that Allah makes it an expiation for him.” [صحيح بخاري : 5640 و صحيح مسلم : 2572]
In another narration, it is mentioned that the Prophet sallallahu alayhi wa sallam said: “Whenever a Muslim is afflicted with any hardship, illness, distress, or grief, even a thorn that pricks him, Allah, through it, forgives his sins.” [صحيح بخاري : 5641، 5642 وصحيح مسلم : 2573]
➋ It is narrated from Sayyiduna Suhayb al-Rumi radi Allahu anhu that the Messenger of Allah sallallahu alayhi wa sallam said: “The affair of the believer is amazing (beloved); all of his matters are good for him, and this is only for the believer. If happiness comes to him, he is grateful, and that is better for him; and if affliction befalls him, he is patient, and that is better for him.” [صحيح مسلم : 2999 [7500]
Therefore, a person should always act with patience and gratitude. The statement of Allah, the Exalted, is: «وَاللَّهُ يُحِبُّ الصَّابِرِينَ» “And Allah loves those who are patient.” [آل عمران : 146]
➌ It is not correct to consider every affliction as a punishment; sometimes it is a means for the elevation of the believer’s ranks.