‏الأيمان : Hadeeth No:4053 Abu Huraira reported Allaah's Messenger (sallAllaahu alayhi wa sallam) as saying: He who took an oath and then found another thing better than (this) should expiate for the oath (broken) by him and do (the better thing)....

‏الذكر والدعاء والتوبة والاستغفار‏ : Hadeeth No:6527 This hadith has been narrated on the authority of 'Asim with the same chain of transmitters....