Explain the difference in usage of G-d's name in parshat Balak

Question

It seems that Bil'am refers to G-d using the name אדונ-י but when G-d appears to him, the name אלוהי-ם is used. For example, compare:

Bemidbar 22:8 Bil'am uses יי ; next verse (9) when G-d speaks to him the word אלוהי-ם is used

verses 13 and 18 Bil'am uses יי, verse 20, G-d appears to him, again - אלוהי-ם.

Each time G-d appears to him, prior to telling Bil'am what to say, the word אלוהי-ם is used.

One "exception" is that when the angel appears, he is called מלאך יי and not מלאך אלהי-ם .

So why do we have this difference in G-d's names, and why is the angel the exception to this pattern?

Answer 1

The main name is the attribute of Justice while the four letter Name is for the attribute of Mercy. The malach appeared to save his life and give him a chance to act properly.

Balak 22:22

וַיִּחַר אַף אֱלֹהִים כִּי הוֹלֵךְ הוּא וַיִּתְיַצֵּב מַלְאַךְ יְהֹוָה בַּדֶּרֶךְ לְשָׂטָן לוֹ וְהוּא רֹכֵב עַל אֲתֹנוֹ וּשְׁנֵי נְעָרָיו עִמּוֹ:

As we see Hashem became angry with Bil'am because of his insistence on not doing what Hashem wanted and deserving the death penalty. As a result, the malach appearing to stop him was an expression of mercy.

As an example

Justice and Mercy

“And Elokim (G-d of Justice) spoke unto Moshe saying: I am YHVH (G-d of Mercy)” (6:2).

Thus, when Hashem forbade Bil'am from cursing the Bnei Yisrael, He did not do so because He was exhibiting mercy, but because He was showing that they did not deserve to be cursed based on the attribute of Justice. When He sent the malach to give Bil'am a final chance, He was exhibiting the trait of Mercy by allowing him a chance to act properly of his own free will. Every reference from 22:22 to 22:35 uses the Name of Hashe (Mercy) for that reason.

As Rav Hirsch translates Balak 23:4

וַיִּקָּר אֱלֹהִים אֶל בִּלְעָם וַיֹּאמֶר אֵלָיו אֶת שִׁבְעַת הַמִּזְבְּחֹת עָרַכְתִּי וָאַעַל פָּר וָאַיִל בַּמִּזְבֵּחַ:

And Elokim let it happen to Balaam ...

Once Bil'am rejected the trait of Mercy, he was again treated with the attribute of Justice

as he explains on verse 5.

וַיָּשֶׂם יְהֹוָה דָּבָר בְּפִי בִלְעָם וַיֹּאמֶר שׁוּב אֶל בָּלָק וְכֹה תְדַבֵּר:

G0d did not grant a vision to which he would then have to give an explanation and meaning in words of what he took the vision to mean, but put in his mouth the actual words he was to say.