Hammam b. Munabbih reported:
This is what Abu Huraira reported to us from Allah's Messenger ( صلی اللہ علیہ وسلم ), and he narrated a hadith and (one) of them is that Allah's Messenger ( صلی اللہ علیہ وسلم ) said: I swear by Allah, it is more sinful in Allah's sight for one of you to persist in an oath regarding his family than payment of its expiation which Allah has imposed upon him (for breaking the oath).