וּבְנֵ֣י הַגְּד֗וּד אֲשֶׁ֨ר הֵשִׁ֤יב אֲמַצְיָ֙הוּ֙ מִלֶּ֤כֶת עִמּוֹ֙ לַמִּלְחָמָ֔ה וַֽיִּפְשְׁטוּ֙ בְּעָרֵ֣י יְהוּדָ֔ה מִשֹּׁמְר֖וֹן וְעַד־בֵּ֣ית חוֹר֑וֹן וַיַּכּ֤וּ מֵהֶם֙ שְׁלֹ֣שֶׁת אֲלָפִ֔ים וַיָּבֹ֖זּוּ בִּזָּ֥ה רַבָּֽה׃ (ס)
But the men of the army whom Amaziah sent back, that they should not go with him to battle, fell upon the cities of Judah, from Samaria even unto Beth-horon, and smote of them three thousand, and took much spoil.
Read midrashic interpretation of II Chronicles 25:13: and classical rabbinic exegesis.