All perfect praise be to Allah, The Lord of The Worlds, and may His peace and blessings be upon our Prophet Muhammad and upon all of his family and companions.

In principle, a Muslim shouldn’t make an oath by Allah save being in need for that, for Allah, The Exalted Said (What means):” And make not Allah, by your oaths, a hindrance to your being righteous and observing your duty unto Him and making peace among mankind. Allah is Hearer, Knower.” [Al-Baqarah/224].

Further, Al-Khateeb As-Shrbini (May Allah have mercy on his soul) said: ”In general, oaths are reprehensible since Allah Said (What means):” And make not Allah, by your oaths, a hindrance” as well as, a Muslim should avoid making many oaths because sometimes he won’t be able to fulfill. Besides, Harmalah reported: I heard Al-Imam Ashafeii’ saying:” I never take an oath by Allah save for performing an obligatory act, act of obedience or quitting a prohibited act.” 

Furthermore, Al-Imam An-Nawawi (May Allah have mercy on his soul) said:” Oaths might be used to emphasize a certain matter or shedding the light on the Greatness of something; in this regard, there are two narrations as follow, Aisha’ (May Allah be pleased with her) narrated, the Prophet (PBUH) said (What means): ”for by Allah (SWT), Allah never gets tired (of giving reward) until you get tired. In addition, He (PBUH) said (What means):” By Allah, if you knew what I know, you would laugh little, weep much.” Further, the reason for making oath is to be in a need for it.” [Mughni Al-Muhtaj vol.6 pp.166].Yet, a person is obliged to fulfill his oath if he was aware of it, save if it was taken on something unlawful. 

Furthermore, the majority of Muslim jurists are of the view that the angry person is accountable for any act of disbelief, murder, taking peoples’ money unjustly, divorce, manumitting of a salve or taking oaths, in this regard Ibn Rajab said:” Whatever an angry person indulged in, will be fully accountable for it, whether it was a divorce, manumitting of a salve or taking an oath.” [Jamai’ Al-Oloum Wal-Hekam vol.1pp.375]

In conclusion, you (Questioner) are obliged to offer oath’s expiation for the Prophet (PBUH) said (What means): ”He who took an oath and (later on) found something better than that should do that, and expiate for (breaking) his vow. [Related by Muslim]

So if you broke your oath, then you are obliged to pay an expiation for each broken one which is: feeding 10 poor Muslims; a Mud (600g of the common food of the country 60-100 piaster value) for each one of them or clothing 10 poor Muslims, but if you couldn’t, then you are obliged to fast three days. And Allah Knows Best.