וַאדֹנָ֤י יְהוִה֙ יַֽעֲזָר־לִ֔י עַל־כֵּ֖ן לֹ֣א נִכְלָ֑מְתִּי עַל־כֵּ֞ן שַׂ֤מְתִּי פָנַי֙ כַּֽחַלָּמִ֔ישׁ וָאֵדַ֖ע כִּי־לֹ֥א אֵבֽוֹשׁ׃
For the Lord GOD will help me; Therefore have I not been confounded; Therefore have I set my face like a flint, And I know that I shall not be ashamed.
Read Jewish philosophy on Isaiah 50:7: Rambam's Guide for the Perplexed, Saadia Gaon, and classical Jewish philosophical sources, free online.