Verse 17: Wherefore the sin of the young men was very great (Gen. 6:11) before the LORD: for men (Mal. 2:8) abhorred the offering of the LORD.
[Therefore, the sin of the lads was great] The sin was multifaceted: They were taking flesh; 1. other, and more than, what was due to them; 2. provided in a manner other than was proper, that is, raw; 3. at a different time, verse 15; 4. in a different manner, that is, by force and threats; 5. with another end, namely, for their lust, verse 14 (Serarius). They are called lads, either, 1. with respect to age, for they were young, which the Scripture calls lads (Mendoza); 2. or rather in sense and understanding (Drusius), manners (Menochius).
The sin of the young men was very great; because they violently took away both man’s and God’s dues, and this before their time, and that with manifest contempt of God and men; and all this merely for the gratifying of their sensual appetite.
[Before the Lord, אֶת־פְּנֵ֣י יְהוָ֑ה] With the faces of the Lord (Montanus). Before Jehovah (Septuagint, Arabic, Munster, Pagnine, Tigurinus, similarly Jonathan); in the sight of the Lord (Junius and Tremellius). This is added, either, 1. because it was immediately against God, and His worship; or, 2. because it was in the holy place; or, 3. (which appears to me more germane) with God as witness and judge. For, even if those sins because of the authority of the priests were covered over, or perhaps were excused by others, or were immune to human censure; nevertheless, recalled to the divine testimony and judgement, they were judged most grievous and shameful. And a thing is called evil, or good, or great, before the Lord, because it is actually and simply such, Genesis 10:9; 13:13; Luke 1:15; for the eyes of God are not able to be deceived (Mendoza).
Before the Lord, that is, even in the place of God’s special presence, where he saw and observed all their miscarriages; which argues the height of impiety and imprudence.
[For men were withdrawing from the sacrifice of the Lord,כִּ֤י נִֽאֲצוּ֙ הָֽאֲנָשִׁ֔ים אֵ֖ת מִנְחַ֥ת יְהוָֽה׃] For men (the people [English]) were contemning, or despising (detesting [Munster]) the sacrifice (oblations [Jonathan, Munster], gift [Junius and Tremellius], food-offering [English]) of the Lord (Pagnine, Montanus, Jonathan, similarly Tigurinus, Dutch, English, Piscator). The gift of Jehovah, that is, the gift that was to be offered according to the law, together with the Eucharistic sacrifice, or the flesh of the slaughtered sheep. It is a Synecdoche of member (Piscator). They began to hold the sacrifices that were for the honor of the Lord in contempt; and to abhor the offering of sacrifices and oblations, with the avarice of the priests in view (Vatablus, similarly Lapide, Sanchez); and since they saw that the customary rites of the sacrifices were not kept (Menochius). The Israelites, so outraged by the license of God’s ministers, carried away from the worship of God and respect for that: see 1 Samuel 2:24 (Junius, Piscator, Malvenda). God so reluctantly bears others’ injuries, especially those that do spiritual hurt to souls, that He complains of those, rather than of His own. Whence He magnifies the sins of the priests, not so much because they were violating the divine honor and worship, but because they were diverting men from the sacrifice of God (Mendoza). Because of the evil life of ministers religion and divine worship are poorly regarded (Drusius). The manifest sins of the priests turn the people from true religion: and for this reason God grievously punishes those sins, both in those that admit them, and in those that connive, 1 Samuel 3:12. Yet by this the Priesthood is not defiled, upon which even at such times the pious piously attend, and which the following things show (Grotius). See here how grievous is the sin of Priests, on account of the scandal that is given to the laity (Grotius). [Others translate this passage otherwise.]
[And the sin of the lads was great, etc., because they were despising the Sacrifice of the Lord (Septuagint)] [As if אֲנָשִׁים/men here does not signify the people, but the priests.] For they had provoked the anger of the Lord by their crime (Arabic); because the men provoked to anger in the sight of God (Syriac). [Nevertheless, a number take it otherwise, as mentioned.] Moreover, נִאֲצוּ, they abhorred, is in the Piel, which intensifies the signification; that is to say, they were vehemently reproaching and blaspheming the sacrifice of Jehovah (Malvenda).
Men abhorred the offering of the Lord; they neglected and abhorred the practice of carrying up sacrifices to be offered, which they knew would be so grossly abused; and which, as they might think, would be rejected and abhorred by God himself; and therefore they would not contribute to the priests’ sin, and the corruption of God’s worship, but judged it better to neglect the thing, than to expose it to the priests’ depravation; wherein yet they erred, as we see, verse 24.
 Hebrew: וַתְּהִ֙י חַטַּ֧את הַנְּעָרִ֛ים גְּדוֹלָ֥ה מְאֹ֖ד אֶת־פְּנֵ֣י יְהוָ֑ה כִּ֤י נִֽאֲצוּ֙ הָֽאֲנָשִׁ֔ים אֵ֖ת מִנְחַ֥ת יְהוָֽה׃  Hebrew: וַתְּהִ֙י חַטַּ֧את הַנְּעָרִ֛ים גְּדוֹלָ֥ה מְאֹ֖ד.  A woodenly literalistic rendering.  See, for example, Leviticus 7:11-15.