Origen of Alexandria

In the whole sequence of Scripture, at any one time they are said to be men and at another time angels. But the one who thinks this will say that just as there are angels among those who are admittedly men, as Zechariah, who says, “I am with you as an angel of God, says the Lord almighty,” and John, of whom it has been written, “Behold, I send my angel before your face,” so also the angels of God, when they are called “men,” are called this because of their work and not because of their nature.