Alsalam wa alaikom wa rahmatuh allah wa barakatuh, I have a question about oaths and promises. Are they the same? For example once I said to my family member I promise not to lower my grade inshaa allah and another time I promise to do my best inshaa allah. Do I have to do kaffara for these promises? Once I also made a promise TO and not BY god that I would study more but didn't what about this. In addition I used to fast three days for other swears but I didn't know that fasting was only allowed if the other options were not available- Do I have to repeat these?
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
A promise is what a person assures that he will do, like him saying ‘I will do such and such’ or ‘I will give such and such’.
As regards the oath, which literally means swearing, according to Islamic terminology this means to confirm a ruling by using a Name of Allaah or one of His Attributes.
Therefore, you should know that what you made was a promise and not an oath, so there is no expiation for what you promised and then broke your promise.
As regards the one who takes an oath by Allaah and then he breaks his oath, then he is obliged to expiate for breaking the oath.
The expiation for an oath is that the one who breaks the oath has a choice to free a slave, or feed ten poor people, or clothe them, and one should not opt for fasting [three days] nor is it sufficient for him to fast unless he is unable to do any of these three aforementioned things. For more benefit on expiation, please refer to Fatwa 102811.
Allaah Knows best.
You can search for fatwa through many choices