Exodus 6:3 Halakhah

וָאֵרָ֗א אֶל־אַבְרָהָ֛ם אֶל־יִצְחָ֥ק וְאֶֽל־יַעֲקֹ֖ב בְּאֵ֣ל שַׁדָּ֑י וּשְׁמִ֣י יְהוָ֔ה לֹ֥א נוֹדַ֖עְתִּי לָהֶֽם׃

and I appeared unto Abraham, unto Isaac, and unto Jacob, as God Almighty, but by My name יהוה a I made Me not known to them.

Read halakhic rulings (Jewish law) on Exodus 6:3: and classical halakhic sources.