12 Now the sons of Eli were worthless men; they had no regard for the Lord. 13 The custom of the priests with the people was that when any man offered sacrifice, the priest's servant would come, while the meat was boiling, with a three-pronged fork in his hand, 14 and 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. So they did at Shiloh to all the Israelites who came there. 15 Moreover, before the fat was burned, the priest's servant would come and say to the man who was sacrificing, "Give meat for the priest to roast; for he will not accept boiled meat from you, but raw." 16 And if the man said to him, "Let them burn the fat first, and then take as much as you wish," he would say, "No, you must give it now; and if not, I will take it by force." 17 Thus the sin of the young men was very great in the sight of the Lord; for the men treated the offering of the Lord with contempt.
Matthew Henry's Commentary on 1 Samuel 2:12-17
Commentary on 1 Samuel 2:11-26
(Read 1 Samuel 2:11-26)
Samuel, being devoted to the Lord in a special manner, was from a child employed about the sanctuary in the services he was capable of. As he did this with a pious disposition of mind, it was called ministering unto the Lord. He received a blessing from the Lord. Those young people who serve God as well as they can, he will enable to improve, that they may serve him better. Eli shunned trouble and exertion. This led him to indulge his children, without using parental authority to restrain and correct them when young. He winked at the abuses in the service of the sanctuary till they became customs, and led to abominations; and his sons, who should have taught those that engaged in the service of the sanctuary what was good, solicited them to wickedness. Their offence was committed even in offering the sacrifices for sins, which typified the atonement of the Saviour! Sins against the remedy, the atonement itself, are most dangerous, they tread under foot the blood of the covenant. Eli's reproof was far too mild and gentle. In general, none are more abandoned than the degenerate children of godly persons, when they break through restraints.