compare the _Summa_ of St. Raymond of Pennafort with the _Summa_ of
St. Thomas Aquinas. When St. Raymond wrote his work, the Church still
followed the criminal code of Popes Lucius III and Innocent III; she
had as yet no notion of inflicting the death penalty for heresy. But
in St. Thomas's time, the Inquisition had been enforcing for some
years the draconian laws of Frederic II. The Angelic Doctor,
therefore, made no attempt to defend the obsolete code of Innocent
III, but endeavored to show that the imperial laws, then authorized
by the Church, were conformable to the strictest justice. His one
argument was to make comparisons, more or less happy, between heresy
and crimes against the common law.

At a period when no one considered a doctrine solidly proved unless
authorities could be quoted in its support, these comparisons were
not enough. So the theologians taxed their ingenuity to find
quotations, not from the Fathers, which would have been difficult,
but from the Scriptures, which seemed favorable to the ideas then in
vogue. St. Optatus had tried to do this as early as the fifth
century,[1] despite the antecedent protests of Origen, Cyprian,
Lactantius and Hilary. Following his example, the churchmen of the
Middle Ages reminded their hearers that according to the Sacred
Scriptures, "Jehovah was a God delighting in the extermination of his
enemies." They read how Saul, the chosen king of Israel, had been
divinely punished for sparing Agag of Amalek; how the prophet Samuel
had hewn him to pieces; how the wholesale slaughter of the
unbelieving Canaanites had been ruthlessly commanded and enforced;
how Elijah had been commended for slaying four hundred and fifty
priests of Baal; and they could not conceive how mercy to those who
rejected the true faith could be aught but disobedience to God. Had
not Almighty God said, "If thy brother, the son of thy mother, or thy
daughter or thy wife, that is in thy bosom, or thy friend, whom thou
lovest as thy own soul, would persuade thee secretly, saying: 'Let us
go and serve strange gods, which thou knowest not, nor thy fathers'
... consent not to him, hear him not, neither let thy eye spare him
to pity or conceal him, but thou shalt presently put him to death.
Let thy hand be first upon him, and afterwards the hands of all the
people."[2]

[1] _De Schismate Donatistarum_, p. iii, cap. vii.

[2] Deut. xiii. 6-9; cf. xvii. 1-6.

Such a teaching might appear, at first sight