12 Now the sons of Eli were sons of Belial; they knew not Jehovah. 13 And the priests' custom with the people was, when any man sacrificed a sacrifice, the priest's servant came, when the flesh was cooked, with a flesh-hook of three prongs in his hand; 14 and he struck it into the pan, or kettle, or cauldron, or pot; the priest took of it all that the flesh-hook brought up. So they did in Shiloh to all the Israelites that came there. 15 Even before they burned the fat, the priest's servant came, and said to the man that sacrificed, Give flesh to roast for the priest, and he will not accept sodden flesh of thee, but raw. 16 If the man said to him, They will immediately burn the fat entire, then take as thy soul desires; he would say [to him], No, but thou shalt give [it] now; and if not, I will take [it] by force. 17 And the sin of the young men was very great before Jehovah, for men despised the offering of Jehovah.
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.