For that seems to be a mere apparition which
appears in its semblance. But it is stated (Luke 3:22) that the "Holy
Ghost descended in a bodily shape as a dove upon Him." Therefore it
was not a real dove, but a semblance of a dove.

Obj. 2: Further, just as "Nature does nothing useless, so neither
does God" (De Coelo i). Now since this dove came merely "in order to
signify something and pass away," as Augustine says (De Trin. ii), a
real dove would have been useless: because the semblance of a dove
was sufficient for that purpose. Therefore it was not a real dove.

Obj. 3: Further, the properties of a thing lead us to a knowledge of
that thing. If, therefore, this were a real dove, its properties
would have signified the nature of the real animal, and not the
effect of the Holy Ghost. Therefore it seems that it was not a real
dove.

_On the contrary,_ Augustine says (De Agone Christ. xxii): "Nor do we
say this as though we asserted that our Lord Jesus Christ alone had a
real body, and that the Holy Ghost appeared to men's eyes in a
fallacious manner: but we say that both those bodies were real."

_I answer that,_ As stated above (Q. 5, A. 1), it was unbecoming that
the Son of God, who is the Truth of the Father, should make use of
anything unreal; wherefore He took, not an imaginary, but a real
body. And since the Holy Ghost is called the Spirit of Truth, as
appears from John 16:13, therefore He too made a real dove in which
to appear, though He did not assume it into unity of person.
Wherefore, after the words quoted above, Augustine adds: "Just as it
behooved the Son of God not to deceive men, so it behooved the Holy
Ghost not to deceive. But it was easy for Almighty God, who created
all creatures out of nothing, to frame the body of a real dove
without the help of other doves, just as it was easy for Him to form
a true body in Mary's womb without the seed of a man: since the
corporeal creature obeys its Lord's command and will, both in the
mother's womb in forming a man, and in the world itself in forming a
dove."

Reply Obj. 1: The Holy Ghost is said to have descended in the shape
or semblance of a dove, not in the sense that the dove was not real,
but in order to show that He did not appear in the form of His
substance.

Reply Obj. 2: It was not superfluous to form a real dove, in which
the Holy Ghost might appear, because by the very reality of the dove
the reality of the Holy Ghost and of His effects is si