Malachim Accepting the Yoke of Heaven

In Birkos Krias Shema:

וכולם מקבלים עליהם עול מלכות שמים זה מזה ונותנים רשות זה לזה להקדיש ליוצרם בנחת רוח:בשפה ברורה ובנעימה קדושה כלם כאחד עונים כאימה ואומרים ביראה

The second phrase, ונותנים רשות זה לזה להקדיש ליוצרם , comes from the passuk in Yeshaya 6:2-3, where it says

שרפים עמדים ממעל לו שש כנפים שש כנפים לאחד בשתים יכסה פניו ובשתים יכסה רגליו ובשתים יעופף  וקרא זה אל זה ואמר קדוש קדוש קדוש

As we say every day in kedusha d'sidra, the Targum of this passuk is

ומקבלין דין מן דין ואמרין:קדיש בשמי מרומא עילאה בית שכינתאקדיש על ארעא עובד גבורתיהקדיש לעלם ולעלמי עלמיא

הוי' צבאות מליא כל ארעא זיו יקריה

It is this Targum ומקבלין דין מן דין ואמרין:קדיש that is the source of what we say in Birkos Krias Shema,
וכולם מקבלים עליהם עול מלכות שמים זה מזה , as explained in many meforshim.

The problem is that Rashi in Yeshaya explains וקרא זה אל זה ואמר to mean that they are careful to enunciate and sing the Kedusha in perfect unison, and to do so, they have to prepare and organize the moment with permission from each other.

וקרא זה אל זה - נוטלין רשות זה מזה שלא יקדים האחד ויתחיל ויתחייב שריפה אלא אם כן פתחו כולם כאחד וזהו שיסד ביוצר אור קדושה כולם כאחד עונים

Elsewhere this is explained to teach us of the mutual respect exhibited by the Malachim.

This is understandable in enunciating the Kedusha.  But I don't understand what the authors of Birkos Kerias Shema meant when they applied this idea to the קבלת עול מלכת שמים of the Malachim- וכולם מקבלים עליהם עול מלכות שמים זה מזה .  As I understand it, קבלת עול מלכת שמים means that you consciously accept upon yourself the yoke of total dedication to the Kingdom of Hashem, and you state that you will fulfill the will of the Ribono shel Olam.  This is something which cannot in any way be received from outside.  Bishlema נותנים רשות זה לזה להקדיש as far as singing the Kedusha, that requires unison and mutual respect among those that are saying Kedusha.  But  קבלת עול מלכת שמים is absolutely personal.  קבלת עול מלכת שמים is an acknowledgment and a pledge of servitude.  It is personal and internal, and it cannot be received.  So why did they move the מקבלין דין מן דין from Kedusha to something that is not in the original passuk at all, קבלת עול מלכת שמים?  And having added it, what does קבלת עול מלכת שמים זה מזה mean?

It's a simple question.  I realize that when we're talking about the Maaseh Merkava, I know nothing, and the words mean things I cannot understand.  But this is Birkos Kerias Shema, and it was put there because we're expected to understand it on some level, not to enunciate words that have no rational meaning to us.  Sot there has to be a simple pshat.  Simple question, simple pshat.  What is the pshat"

A dear friend gave me two answers, one based on the Siddur Yaavetz and one on the Rambam in Moreh.  I finally feel I can say Birkos Kerias Shema with some understanding.  I asked him to write it up; maybe he will.  I'm going to wait a day or two to see, because his writing is, in my opinion, aesthetically peerless and intellectually superb.

.....................

Ok, I haven't heard from my brilliant friend, so here's a very pale rendition of what he said.

One; the Siddur Yaavetz says, clearly, that the Kabalas Ol Malchus Shamayim IS the shira of kedusha.
(Here is what the Yaavetz says.

מקבלים. נקשר עם זה מזה. ר״ל נוטלין רשות זה מזה לומר קבלת עול מלכות שמים שהיא הקדושה שמקדישין כמו שמבאר והולך. ומיוסד על הפסוק וקרא זה אל זה וגו׳. ומתרגמינן ומקבלין דין מן דין

Two: the malachim here are the spheres of kedusha, becoming more mixed with gashmius on the way "down." Mekablim means that each sphere is enlivened and made real by a relationship with the sphere "above" it.

What I liked especially about his second pshat is that it really expains mekablim.  Each malach, in descending rank, receives its tafkid and power from the malach above it.  Kabalas Ol Malchus Shamayim, for what we call Malachim, is not a statement, it is their definition and their function.

A friend and reader, Rav Dr Nachum J, said the following (improved by punctuation.)  It's not far from what my other friend said.

Malaachim are divine forces /emanation/ consequences of the divine will/ thought/desire/plan.  When we say that they consult with each other we mean that they are consistent/single-minded/coordinated etc
Shma is Kabalas Ol Malchus Shamayim (hereinafter, KOMS.)  Birkot KS are preparation for KOMS.  We remind ourselves that KOMS is NOT " me and god against the world," but rather, i am joining with all the rest of creation, in harmony, to fulfill the divine will, and not my own subjective fantasy of what that divine will should be.

Another friend, R' Dr. Meir Z, said something similar.  Each malach, and each person, stands on his own level.  In order to serve the will of Hashem, each has to learn from the other.  Certainly the lower ones have to learn from the higher, and perhaps even the higher learn from the lower what KOMS means when you are distant from the Shechina, and there is more personal initiative involved.