The special sin chargeable against Israel in the past had been the introduction into the sanctuary, while the priests were engaged in sacrifice, of strangers—aliens (Revised Version); literally, sons of a stranger—uncircumcised in heart and uncircumcised in flesh, in express contravention of Jehovah's covenant.
Ewald, Havernick, Hengstenberg, Schroder, and Currey restrict the designation "strangers" to unfaithful and unauthorized priests, who, as in the days of Israel's apostasy, notoriously under Jeroboam (1 Kings 12:31; 2 Chronicles 11:15), may, in the confluence of idolatries that took place in Jerusalem during the reigns of Ahaz (2 Kings 16:3, 2 Kings 16:4, 2 Kings 16:10-15; 2 Chronicles 28:2-4, 2 Chronicles 28:23-25) and Manasseh (2 Kings 21:2-7, 2 Kings 21:11, 2 Kings 21:15; 2 Chronicles 33:2-7), have been admitted to participate in the temple services; but Kliefoth, Delitzsch, Keil, Smend, and Plumptre, with better judgment, recognize in the "strangers" foreigners who had not incorporated themselves with Israel by submitting to circumcision, but, though dwelling in the midst of Israel, were still uncircumcised heathen in both heart and flesh.
With regard to these foreigners, the Law of Moses (Le 17:8,10) enacted that, by accepting circumcision, they might become members of the Israelitish commonwealth, but that without this they could not be permitted to partake of the Passover, the highest symbol of national and religious unity (Exodus 12:48, Exodus 12:49).
Nevertheless, it was open to them, on giving a certain measure of obedience to the Law (Exodus 12:19; Exodus 20:10; Le Exodus 17:10, Exodus 17:12; Exodus 18:26; Exodus 20:2; Exodus 24:16, 22), to enter the sanctuary and present all sorts of offerings to Jehovah (Le 17:8; Numbers 15:14, Numbers 15:29) Hence Israel's offence had not been the admission of such "sons of the stranger" into the sanctuary, but the admission of them without insisting on the above specified conditions, in other words, the admission of such as not only lacked the bodily mark of circumcision—which would not have excluded them—but were destitute as well of the first elements of Hebrew piety, i.
e. were as uncircumcised in heart as they were in the flesh. The sanctioning of such within the temple courts, while Jehovah's bread, the fat and the blood, was being offered, i.e. while sacrificial worship was being performed, was not simply a desecration of the "house," but was an express violation of the covenant Jehovah had made with Israel with reference to these very "sons of the stranger."