What did the rabbis feel about the practive of invoking angels?

It is possible, on the other hand, that a practice grew up among the people of invoking angels. That it was deprecated by the Rabbis is evident from the words they put into the mouth of God: "If trouble befall a man, let him not cry to Michael or Gabriel; but let him cry to Me and I will answer him at once."[1]

footnotes [1] BT Berakhot 13a