The books of Ezra and Nehemya put a new emphasis on the sin of intermarriage, including seemingly harsh responses. The leaders of Shivat Tzion seem to present the sin somewhat differently than earlier Biblical works.
According to the Torah, exogamy is prohibited so as not to lead one’s children toward idolatry. In contrast, the leaders of Shivat Tzion seem to speak with a different point of emphasis, introducing new terminology implying that the sin is not so much about the concern for idolatry or otherwise sinful lifestyle, but runs counter to the holiness of the Jew, an act of betrayal.
For arguably the first time in history, during the period of Ezra and Nehemya, the temptation of idolatry no longer looms large. Therefore, whereas Devarim and Melakhim tended to stress the lure of paganism, Ezra, Nehemya and Malakhi, no longer confronting this threat, emphasized the inherently objectionable nature of the proscription.
What does emerge with clarity from Ezra-Nehemya is that there are times, especially when the Jewish community faces an existential challenge, when an unyielding approach is necessary. Although many might take offense to such a “heavy-handed” response, sometimes proper leadership demands an approach that closely follows the firm stand taken by Ezra and Nehemya.