Angels are not always intermediaries

Ohr HaChaim(Shemos 23:20) הנה אנכי שולח מלאך לפניך, "Here I am sending an angel ahead of you, etc." The author feels that the angel described here is not an intermediary, one of G'd's ministering angels, but the "great angel," the one who redeemed the patriarchs, a concept familiar to Kabbalists. He says that by definition we do not recognise a force as an intermediary, i.e. an independent power to whom we have to show respect and obeisance. [I believe that the reason for this statement is that reading verses 21 and 22 could lead one to believe that G'd inserted some angel between Himself and us. Ed.] Only at the end of time, will the world recognise that G'd and His name (those speaking in His name, such as angels) are One; compare Zachariah 14,9.

Ohr HaChaim (Shemos 23:20) אור החיים על שמות פרק כג פסוק כ

(כ) הנה אנכי וגו' פירוש מלאך זה, הוא המלאך הגואל את האבות, לא משרת ממשרתיו אלא מלאך גדול, כידוע למשכילים כי אין אנו מכירים מלאך אמצעי, אלא הוא יתברך ושכינת עוזו המתיחדת עמו, בסוד ה' אחד ושמו אחד (זכריה יד ט):

 Lekutei Mohoran (11:5:3)There is also the aspect of Shadai of the weekdays. For even on the weekdays there are restrictions, from one work to the next. This corresponds to Metat, whose rule is the six days of the week, corresponding to the six orders of the Mishnah (Tikkuney Zohar #18). For [Metat’s] name is like that of his Master’s, as is written (Exodus 23:21), “because My Name is in him.” This is the lower unification. In other words, the Holy One, blessed-be-He, clothes Himself in Metat during the six days of the week and rules the world through him.