1 Samuel 2:13-14

13and the custom of the priests with [the sacrifices of] the people. When any man was offering a sacrifice, the priest’s servant would come while the meat was boiling, with a three-pronged [meat] fork in his hand;

14then he would thrust it into the pan, or kettle, or caldron, or pot; everything that the fork brought up the priest would take for himself. This is what they did in Shiloh to all [the sacrifices of] the Israelites who came there.