But keeping to promises is another thing entirely.
It's not wise to make promises when you are over excited about something or perhaps when you are even not in your normal state of mind because if you do, you might promise something that you will not find very easy to fulfill at the end when you are finally in that comfortable state of mind. I don't think that guy can fulfill that promise because if he would done so, then he would at give even if it's not up to what he promised.
It happens even when the person is not excited that promises get tougher to fulfill as the day creeps by. His friend may have all he said in mind, and also tells himself that the money would get to Op someday, maybe when next he wins. Sometimes, it's better to be happy for the assurance, regardless of the delay in making it happen.