This meaning is also established by the Sunnah.

In the two Sahīhs, Hammām narrates from Abū Hurayrah that the Messenger of Allah, may Allah bless him and grant him peace, said:

“For one of you to persist in an oath concerning his family is more sinful in Allah’s sight than to offer the expiation Allah has prescribed for him.”

Al-Bukhārī also narrated through ‘Ikrimah, from Abū Hurayrah, that the Prophet, may Allah bless him and grant him peace, said:

“Whoever stubbornly persists in an oath concerning his family incurs a greater sin.”

The Prophet, may Allah bless him and grant him peace, thus explained that stubbornly persisting in an oath concerning one’s family is graver than making expiation. Obstinacy means persisting in a dispute; hence a man who persists in a dispute is called obstinate. This is why scholars call this a “vow of obstinacy and anger”: a person persists obstinately until he binds himself by the vow, then persists in refusing to break it. The Prophet, may Allah bless him and grant him peace, thus made clear that stubbornly persisting in an oath is more sinful than making expiation. This applies generally to all oaths.

Furthermore, the Prophet, may Allah bless him and grant him peace, said to ‘Abd al-Rahmān ibn Samurah:

“If you swear an oath and then see that another course is better, do what is better and make expiation for your oath.”

Both al-Bukhārī and Muslim recorded this in their Sahīhs. Another version in the two Sahīhs reads:

“Make expiation for your oath and do what is better.”

Muslim also narrated in his Sahīh, from Abū Hurayrah, that the Messenger of Allah, may Allah bless him and grant him peace, said:

“Whoever swears an oath and then sees that another course is better should make expiation for his oath and do what is better.”

Another version reads:

“He should do what is better and make expiation for his oath.”

This is an indefinite expression