ETHNIC. - A Greek term (ἐθνικός, Vulgate ethnicus or gentilis) with which Hellenistic Jews designated the pagan, a member of the "nations" that did not profess monotheism.
This is the non-exclusive but prevalent sense in the Bible of ἐθνικός (as a noun): Mt. 5:47; 6:7; 13:17; as a plural it is synonymous with τὰ ἐθνή, which in the Septuagint translates the Hebrew haggājim (Ex. 34:24; Lev. 18:24, etc.; Is. 9:1), cf. Mt. 4:15; 6:32 and passim; in opposition to the Jews: Rom. 3:39; 9:24, etc.; Lk. 2:32; Acts 26:17, 23.
In the Old Testament there is the clearest distinction between the people of God (ὁ λαός) and "the nations" (τὰ ἐθνή), with the prohibition of marriage relations and treaties of friendship (Ex. 34:16; Esd. 9-10; Is. 7:17; 30; 31; Jer. 2:15; Ez. 16:28, etc.) and with exclusion from worship and from the Temple, because of the grave danger of idolatrous influence.
Distinction and separation, not hatred; the Mosaic legislation prescribes justice and benevolence toward ethnics (Ex. 22:21; 23:9; Lev. 19:33 ff.; Deut. 10:18 ff., etc.; cf. H. Lesêtre, Etranger, in DB, II, col. 204); they could embrace the Jewish religion (v. proselutti); and the prophets announce their aggregation to the messianic kingdom: Is. 2:2; 42:6; 49:6; 60:3; Zach. 2:15; 8:23; Mal. 1:11, etc. In the persecutions suffered upon the return from exile (Neh. 5:8; 9:2; 13:1-3) and particularly by the Seleucids (I-II Maccabees) there developed among the Jews that hatred against the "ethnics" or "gentiles," which the Pharisees consecrated in their program.
In the New Testament the distinction remains (cf. Mt. 15:24; Gal. 2:15, etc.) and the Church appears distinct just as the Jews were from the world of the gentiles (Mt. 18:17; M.-J. Lagrange); but Jesus eliminated the ancient barrier (Eph. 2:14) and called all ethnics to his kingdom (cf. Mt. 28:19; Mk. 16:15; Lk. 24:47;
Rom. 1:17, etc.). The Apostles carried out this universal mission received from Jesus (cf. Acts. 8:10-11, etc.).

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Francesco Spadafora