Tirmidhi

Explanation:
1:
It is understood from this that by performing the prayer (salah), a person continues to be cleansed and purified from minor sins (saghirah),
but the condition for this is that the prayer must be performed according to the Sunnah,
and the prayer should be offered with the understanding and intention that it is indeed prayer.

Hadith Commentary:
(1)
The Murji’ah have argued from the apparent meaning of this hadith that all major and minor sins are forgiven through good deeds. However, the majority of Ahl al-Sunnah hold the position that only minor sins are forgiven by them, because although this hadith is general and absolute in its wording, another hadith has restricted and specified it.
As in one hadith, it is stated that the five daily prayers, from one Friday to the next, and from one Ramadan to the next, become expiation for sins, provided that major sins are avoided.
(Sahih Muslim, al-Taharah, Hadith: 552(233))
A narration in Jami‘ al-Tirmidhi states that the five daily prayers and from one Friday to the next are expiation for the sins committed in between, provided that major sins are not committed.
(Jami‘ al-Tirmidhi, al-Salat, Hadith: 214) (2)
Previously, Imam al-Bukhari rahimahullah established a chapter with these words:
“Prayer is an expiation for sins.”
The purpose was to clarify this particular quality of prayer, that it erases sins, regardless of whether the prayer is obligatory (fard) or supererogatory (nafl).
At this point, a question arises: For those acts that are included among a servant’s obligations and responsibilities, by fulfilling them a person may become deserving of reward or be protected from Allah’s displeasure, but it is not necessary that he becomes worthy of further reward and honor.
Imam al-Bukhari rahimahullah brought the aforementioned chapter to dispel this misconception, that there is no deficiency in Allah’s treasures; in fact, obligatory prayer has a greater capacity to become expiation for sins than supererogatory prayer, because obligatory acts are more significant in the sight of Allah than supererogatory acts, and the obligations are more beloved to Allah, as is mentioned in another hadith: “My servant does not draw near to Me with anything more beloved to Me than the obligations I have enjoined upon him.”
(Sahih al-Bukhari, al-Riqaq, Hadith: 6502) (3)
In some manuscripts of Sahih al-Bukhari, this chapter heading appears as follows:
“If the five daily prayers are performed on time, they are expiation for sins, whether performed in congregation or individually.”
Some have objected to this heading, saying that the Imam should not have included the words “or otherwise,” because this would diminish the importance of congregational prayer.
This objection is not valid, because the Imam intends to clarify that if, due to some excuse, one is unable to perform prayer in congregation, then prayer performed individually will also be expiation for sins.
This does not mean at all that congregational and individual prayers are equal.
And Allah knows best.
(4)
Previously, with reference to Sahih Muslim, this hadith was mentioned that the five daily prayers are expiation for sins, provided that major sins are avoided.
Apparently, this hadith seems to conflict with the given example, because after bathing five times, no dirt would remain at all; if any does remain, it would be very little. Similarly, by performing the prayers, will all sins be forgiven, or will some minor sins remain?
The answer to this apparent contradiction is that in the hadith, minor sins are likened to dirt, whether they are few or many, while major sins are like wounds and internal diseases, which are only forgiven through repentance and turning to Allah.
By bathing, only external dirt can be removed; diseases cannot be treated by it.
Similarly, by performing prayer, minor sins can be erased, but major sins will not be forgiven.
(5)
The statement of Allah, the Exalted, is:
﴿ إِن تَجْتَنِبُوا كَبَائِرَ مَا تُنْهَوْنَ عَنْهُ نُكَفِّرْ عَنكُمْ سَيِّئَاتِكُمْ ﴾ “If you avoid the major sins which you are forbidden, We will remove from you your minor sins.”
(al-Nisa: 4:31)
In view of this verse, an objection is raised regarding the aforementioned hadith: If minor sins are erased merely by avoiding major sins, then for what type of sins do the prayers serve as expiation?
The answer to this objection is that Allah, the Exalted, erases minor sins through the prayers themselves, because not performing prayer is itself a major sin; therefore, without performing the prayers, it is not possible to avoid major sins.

Hadith Commentary:
Benefits and Issues:
By performing prayer (salah), a person's minor sins (saghirah) are forgiven, because the effects of minor sins manifest on the outward body, and thus their removal is easy. Just as if dirt on the body does not penetrate the pores or if filth is not absorbed into the clothing, then washing it is easy. However, if the dirt that attaches to the body seeps inside, then even cleaning it with soap is not easy. The effects of major sins (kabirah) impact a person's heart, and therefore, they are not forgiven except through repentance (tawbah) or the special mercy of Allah Ta'ala.

463. Commentary:

➊ Although a group of scholars has interpreted «خَطَايَا» here to mean minor sins (saghā’ir), this does not align with the apparent meaning of the hadith; “khataaya” (sins) is general, whether they are minor or major (kabā’ir), because Allah’s mercy is far more expansive than that.

➋ Although repentance (tawbah) is indeed a cause for forgiveness, forgiveness is not exclusively dependent upon it such that, without it, forgiveness could never occur. However, it is certain that with sincere repentance, forgiveness becomes assured.