1 Samuel 2:13-14

131and the custom of the priests with the people. When any man was offering a sacrifice, the priest’s servant would come while the meat was boiling, with a three-pronged fork in his hand.

14Then he would thrust it into the pan, or kettle, or caldron, or pot; all that the fork brought up the priest would take for himself. Thus they did in Shiloh to all the Israelites who came there.