Again, Ezechiel began
to prophesy in "his thirtieth year," as we read Ezech. 1:1.

Secondly, because, as Chrysostom says (Hom. x in Matth.), "the law
was about to pass away after Christ's baptism: wherefore Christ came
to be baptized at this age which admits of all sins; in order that by
His observing the law, no one might say that because He Himself could
not fulfil it, He did away with it."

Thirdly, because by Christ's being baptized at the perfect age, we
are given to understand that baptism brings forth perfect men,
according to Eph. 4:13: "Until we all meet into the unity of faith,
and of the knowledge of the Son of God, unto a perfect man, unto the
measure of the age of the fulness of Christ." Hence the very property
of the number seems to point to this. For thirty is product of three
and ten: and by the number three is implied faith in the Trinity,
while ten signifies the fulfilment of the commandments of the Law: in
which two things the perfection of Christian life consists.

Reply Obj. 1: As Gregory Nazianzen says (Orat. xl), Christ was
baptized, not "as though He needed to be cleansed, or as though some
peril threatened Him if He delayed to be baptized. But no small
danger besets any other man who departs from this life without being
clothed with the garment of incorruptibility"--namely, grace. And
though it be a good thing to remain clean after baptism, "yet is it
still better," as he says, "to be slightly sullied now and then than
to be altogether deprived of grace."

Reply Obj. 2: The profit which accrues to men from Christ is
chiefly through faith and humility: to both of which He conduced by
beginning to teach not in His boyhood or youth, but at the perfect
age. To faith, because in this manner His human nature is shown to be
real, by its making bodily progress with the advance of time; and lest
this progress should be deemed imaginary, He did not wish to show His
wisdom and power before His body had reached the perfect age: to
humility, lest anyone should presume to govern or teach others before
attaining to perfect age.

Reply Obj. 3: Christ was set before men as an example to all.
Wherefore it behooved that to be shown forth in Him, which is becoming
to all according to the common law--namely, that He should teach
after reaching the perfect age. But, as Gregory Nazianzen says (Orat.
xxxix), that which seldom occurs is not the law of the Church; as
"neither does one swallow make the spring." For