Question
What is the meaning of Ex. 6:3, "I revealed Myself to Abraham,Isaac, and Jacob as E-L SH-A-D-AI, and didn’t make Myself knownto them by My Name Y-H-V-H"?
Answer
The commentators explain that the Name Y-H-V-H implies that G-d keeps His promises, whereas the promises made to the Patriarchs had not yet been entirely fulfilled. (The Name Y-H-V-H itself WAS known to them — e.g., Gen. 15:2.) G-d was best known to the Patriarchs as SH-A-D-AI ("Almighty") because of His miracles. The commentators also point out that the Patriarchs saw G-d in visions (va-era: "I was seen"); He did not make Himself "known" (nodati) to them as He did to Moses.