Metatron?

“Behold, I send an angel before you to guard you on the way and to bring you to the place which I have prepared.
Beware of him and listen to his voice, do not rebel against him, for he will not bear your iniquity, for my name is in the midst of the battles.
But if you will indeed listen to his voice and do all that I say, then I will avenge your affliction and afflict your afflictions.
For my angel will go before you and bring you…’

Rashi says this is from Matron…
What is a call to worship God through the medium of an angel?
At least not to annoy him?

I really don’t understand.
I’m asking a simple, basic question.