בָּגְדָ֣ה יְהוּדָ֔ה וְתוֹעֵבָ֛ה נֶעֶשְׂתָ֥ה בְיִשְׂרָאֵ֖ל וּבִירֽוּשָׁלִָ֑ם כִּ֣י ׀ חִלֵּ֣ל יְהוּדָ֗ה קֹ֤דֶשׁ יְהוָה֙ אֲשֶׁ֣ר אָהֵ֔ב וּבָעַ֖ל בַּת־אֵ֥ל נֵכָֽר׃
Juda hat verräterisch gehandelt, und in Israel und in Jerusalem wird ein Greuel begangen; Denn Juda hat die Heiligkeit des HERRN entweiht, die er liebt, und die Tochter eines fremden Gottes geheiratet.
Rashi on Malachi
for Judah has profaned himself, who was the holy one of the Lord, the first of His grain.
Rashi on Malachi
and married the daughter of a foreign god that they married gentile women in Babylon, and even the priests, as is delineated in the Book of Ezra (chap. 9 and 10). Our Sages said that Malachi is Ezra.