Prayers for Kitty?

Silly as it sounds, I need prayers for my almost-16-yr-old kitty tonight. He hasn't eaten anything at all today, not even a few drops of canned milk or the tablespoon of vanilla ice cream I thought would tempt him. Might be a hairball but I can't get him to eat his fave hairball crunchies...if I remember right, he sort of goes through this once or twice a year, but it always worries me.