The identification of an unsound Monarchianism with Judaism is illustrated in the 1st Apology of Justin Martyr, e.g. in § lxxxiii. (Reeves’ Trans.).  “The Jews, therefore, for maintaining that it was the Father of the Universe who had the conference with Moses, when it was the very Son of God who had it, and who is styled both Angel and Apostle, are justly accused by the prophetic spirit and Christ Himself, for knowing neither the Father nor the Son; for they who affirm the Son to be the Father are guilty of not knowing the Father, and likewise of being ignorant that the Father of the Universe has a Son, who, being the Logos and First-begotten of God, is God.”