Ninety million angels with nothing to do

The following section of the Haggadah, taken from the common traditional version, argues strenuously against the intervention of heavenly or human intermediaries in the tenth plague, and possibly in the entire progression of the Exodus: 

וַיּוֹצִאֵנוּ ה' מִמִּצְרַיִם. לֹא עַל־יְדֵי מַלְאָךְ, וְלֹא עַל־יְדֵי שָׂרָף, וְלֹא עַל־יְדֵי שָׁלִיחַ, אֶלָּא הַקָּדוֹשׁ בָּרוּךְ הוּא בִּכְבוֹדוֹ וּבְעַצְמוֹ. שֶׁנֶּאֱמַר: וְעָבַרְתִּי בְאֶרֶץ מִצְרַיִם בַּלַּיְלָה הַזֶּה, וְהִכֵּיתִי כָּל־בְּכוֹר בְּאֶרֶץ מִצְרַיִם מֵאָדָם וְעַד בְּהֵמָה, וּבְכָל אֱלֹהֵי מִצְרַיִם אֶעֱשֶׂה שְׁפָטִים. אֲנִי ה'.

"The Lord freed us from Egypt" - not through an angel and not through a seraph and not through a messenger, but directly by the Holy One, blessed be He, Himself, as it is stated (Ex. 12:12); "And I will pass through the Land of Egypt on that night and I will smite every firstborn in the Land of Egypt, from men to animals; and with all the gods of Egypt, I will make judgments, I am the Lord." 

In the Yemenite version of the Haggadah, an intriguing addendum follows immediately: 

Source:  פניני משה - הגדה של פסח נוסח תימן - משה קלזן

"Nine thousand myriads" (ninety million) angels descended with God to execute the Egyptian firstborns, but God sidelines them, insisting on carrying out the punishment himself. This late midrashic tradition was apparently popular among Yemenite Jews. A very close parallel can be found in the thirteenth-century Yemenite anthology Midrash Hagadol, where it is placed in the context of the splitting of the Red Sea (Ex. 14:25):

Source: Midrash Hagadol Sefer Shemot, ed. M. Margaliot (Mossad Harav Kook, 1967), p. 277.

Preserved up to the present time in Yemenite liturgy and lore, the ninety million demons have an antecedent in the (also relatively late) Targum Pseudo-Jonathan (Ex. 12:12):

וְאִתְגְּלֵי בְּאַרְעָא דְמִצְרַיִם בִּשְׁכִינַת יְקָרִי בְּלֵילְיָא הָדֵין וְעִמִּי תִּשְׁעִין אַלְפִין רִבְוָון מַלְאָכִין מְחַבְּלִין וְאֶקְטוֹל כָּל בּוּכְרָא בְּאַרְעָא דְמִצְרַיִם מֵאֱנָשָׁא וְעַד בְּעִירָא

And I will be revealed in the land of Egypt in the majesty of my glory on that night, and with me ninety thousand myriads of destroying angels; and I will slay all the firstborn in the land of Egypt . . .

In the previous two sources, the ninety million are called "Angels of Destruction" (מלאכי חבלה), or demons.

The tradition to which Pseudo-Jonathan alludes seems to have made its way into the Haggadot of several medieval European Jewish communities as well. The twelfth-century French halakhic-liturgical work Mahzor Vitry (p. 293), from the school of Rashi, raises but critiques the practice. The author attests that the Jews of Provence accepted it, while those of Eretz Yisrael did not. He himself rejects the insertion because it is absent from the Tannaitic Mekhilta (which includes strong parallels to this section of the Haggadah), and due to theological and stylistic objections he has to some of its content: 

Why was it so important to the Haggadah to negate the role of messengers in the Exodus, to such an extent -- at least in the alternative version -- as to conjure up the image of ninety million demons ready to execute the firstborns but prevented from doing so? What compelled the rabbis to resist so adamantly the idea that God had semi-divine or human assistance in the Exodus?

In fact, the Haggadah itself appears to contradict that very notion:

רַבִּי אֱלִיעֶזֶר אוֹמֵר: מִנַּיִן שֶׁכָּל־מַכָּה וּמַכָּה שֶׁהֵבִיא הַקָּדוֹשׁ בָּרוּךְ הוּא עַל הַמִּצְרִים בְּמִצְרַיִם הָיְתָה שֶׁל אַרְבַּע מַכּוֹת? שֶׁנֶּאֱמַר: יְשַׁלַּח־בָּם חֲרוֹן אַפּוֹ, עֶבְרָה וָזַעַם וְצָרָה, מִשְׁלַחַת מַלְאֲכֵי רָעִים.

Rabbi Eliezer says: How can you know that each and every plague the Holy One brought upon the Egyptians in Egypt was in fact made up of four plagues? For it is said, “His fury was sent down upon them, great anger, rage, and distress, a company of messengers of destruction.”

Whatever the reason for the rhetorical campaign against intermediaries, the Haggadah reflects, and amplifies, a tension that is already present within the Torah itself.  

In the context of the tenth plague, some verses, spoken in God's voice, emphatically use the singular (Ex. 11:4; 12:12; 12:29), as noted by Mekhilta. On the other hand, there also seems to be a role in the story for a "destroyer" (Ex. 12:13; 12:23). And in Numbers (20:16), there is an explicit reference to a "messenger" who assisted in freeing the Israelites.

But our "not through an angel" passage, with colorful emphasis in the Yemenite version, takes a strident stance in one direction. Closely related to this, I believe, is the fact that the role of Moses himself is severely diminished in the Haggadah's narrative. After all, he was God's messenger to Pharaoh and the Israelites and should have had a leading place in the closing credits of the Exodus.

The Haggadah is intent on removing any doubt as to who was responsible for the Exodus. It goes without saying that angels, demons, and human intermediaries have a prominent role throughout the Bible, even with reference to the Exodus. But the Seder night, when we recite and (try our best to) relive our national foundation story, is meant to stand apart. At that time, there is no room at the table for angelology, cosmological intermediaries, radical materialism, or metaphysical chains of being. There is only God, Israel, and redemption, both national and personal.