Is an oath binding if the other party did not hear it?

If your friend did not show up at the appointed time and you subsequently dealt with him or gave him money, then you have broken your oath. The person sworn upon has no bearing on this, whether he heard the oath or not. We advise you to offer expiation for your oath and to deal with your friend, for it is narrated in the Two Sahihs that the Messenger of Allah, peace and blessings be upon him, said: "By Allah, if Allah wills, I do not swear an oath and then see something better than it, but that I expiate for my oath and do that which is better, or I do that which is better and expiate for my oath."