Swearing to Destroy Another's Possessions

My brother constantly takes my bicycle and it always gets damaged while he’s using it. I swore that if he touches my bicycle again, I would destroy various items of his that are dear to him. He used my bicycle again and damaged it. I am obligated to uphold my oath, but I regret it because it will cause conflict at home and our parents will be very upset. So, what should I do?

You do not have the right to destroy your brother's possessions even if you swore an oath and he damaged yours, especially not in this case. You should urgently seek annulment of vows from a qualified Rabbi. This cannot be done via email, as every moment the oath remains, it could potentially lead to unfortunate events, God forbid. In general, one must be very careful not to make vows or take oaths, even if they are true, and certainly not on something you cannot fulfill. If, God forbid, a vow or oath slips out of your mouth, it should be annulled as quickly as possible.

Shulchan Aruch (Yoreh De'ah, Chapter 236).