כֹּֽה־אָמַ֧ר יְהוָ֛ה גֹּאַלְךָ֖ קְד֣וֹשׁ יִשְׂרָאֵ֑ל אֲנִ֨י יְהוָ֤ה אֱלֹהֶ֙יךָ֙ מְלַמֶּדְךָ֣ לְהוֹעִ֔יל מַדְרִֽיכֲךָ֖ בְּדֶ֥רֶךְ תֵּלֵֽךְ׃
Thus saith the LORD, thy Redeemer, The Holy One of Israel: I am the LORD thy God, Who teacheth thee for thy profit, Who leadeth thee by the way that thou shouldest go.
Read halakhic rulings (Jewish law) on Isaiah 48:17 from the Mishneh Torah and classical halakhic sources, free online.