Shaykh Abdul Sattar al-Hammad
Hadith Commentary:
(1)
According to one narration, the beginning of this hadith is as follows: Sayyidah Aisha radi Allahu anha states that by "vain oaths" (laghw qasms) are meant those oaths which a person utters as a habitual expression in speech, such as "No, by Allah" (la wallah) and "Yes, by Allah" (bala wallah).
(Sahih al-Bukhari, al-Tafsir, Hadith: 4613) (2)
The purpose of Imam Bukhari rahimahullah is that there is no expiation (kaffarah) for such vain oaths, as the Noble Qur'an has explicitly stated this.
When Sayyidah Aisha radi Allahu anha was slandered, among those who accused her was Hazrat Mistah, whom Hazrat Abu Bakr radi Allahu anhu used to support financially.
Out of a sense of honor, he swore that he would never spend anything on him again.
Upon this, Allah the Exalted revealed this verse:
"And let not those among you who possess virtue and wealth swear not to give to their relatives, the needy, and those who have emigrated in the way of Allah; let them pardon and overlook. Do you not love that Allah should forgive you?" (al-Nur: 22/24)
After the revelation of this verse, Hazrat Abu Bakr al-Siddiq radi Allahu anhu immediately submitted to this command and began to help him even more than before.
(Fath al-Bari: 11/631)
Perhaps Imam Bukhari rahimahullah has alluded to that narration in which the explanation of "vain oath" (yamin laghw) is given.
And Allah knows best.
Source: Hidayat al-Qari: Commentary on Sahih Bukhari, Urdu, Page: 6621