Midrash for Isaiah 45:21

הַגִּ֣ידוּ וְהַגִּ֔ישׁוּ אַ֥ף יִֽוָּעֲצ֖וּ יַחְדָּ֑ו מִ֣י הִשְׁמִיעַ֩ זֹ֨את מִקֶּ֜דֶם מֵאָ֣ז הִגִּידָ֗הּ הֲל֨וֹא אֲנִ֤י יְהוָה֙ וְאֵֽין־ע֤וֹד אֱלֹהִים֙ מִבַּלְעָדַ֔י אֵֽל־צַדִּ֣יק וּמוֹשִׁ֔יעַ אַ֖יִן זוּלָתִֽי׃

Declare ye, and bring them near, Yea, let them take counsel together: Who hath announced this from ancient time, And declared it of old? Have not I the LORD? And there is no God else beside Me, A just God and a Saviour; There is none beside Me.

Tanna Debei Eliyahu Rabbah