St. Thomas in this passage makes a mere comparison serve as an argument. He does not seem to realize that if his reasoning were valid, the Church could go a great deal further, and have the death penalty inflicted in many other cases.
The fate of the relapsed heretic had varied from Lucius III to Alexander IV. The bull _Ad Abolendam_ decreed that converted heretics who relapsed into heresy were to be abandoned to the secular arm without trial.[1] But at the time this Decretal was published, the _Animadversio debita_ of the State entailed no severer penalty than banishment and confiscation. When this term, already fearful enough, came to mean the death penalty, the Inquisitors did not know whether to follow the ancient custom or to adopt the new interpretation. For a long time they followed the traditional custom. Bernard of Caux, who was undoubtedly a zealous Inquisitor, is a case in point. In his register of sentences from 1244 to 1248, we meet with sixty cases of relapse, not one of whom was punished by a penalty severer than imprisonment. But a little later on the strict interpretation of the _Animadversio debita_ began to prevail. In St. Thomas's time it meant the death penalty; and we find him citing the bull _Ad Abolendam_[2] as his authority for the infliction of the death penalty upon the relapsed, penitent or impenitent, in ignorance of the fact that this document originally had a totally different interpretation.
[1] Decretals, in cap. ix, _De hæreticis_, lib. v, tit. vii.
[2] _Summa_, IIa IIae, quæst. ix, art. 4: _Sed contra_.
His reasoning therefore rests on a false supposition. He advocates the death penalty for the relapsed in the name of Christian charity. For, he argues, charity has for its object the spiritual and temporal welfare of one's neighbor. His spiritual welfare is the salvation of his soul; his temporal welfare is life, and temporal advantages, such as riches, dignities, and the like. These temporal advantages are subordinate to the spiritual, and charity must prevent their endangering the eternal salvation of their possessor. Charity, therefore, to himself and to others, prompts us to deprive him of these temporal goods, if he makes a bad use of them. For if we allowed the relapsed heretic to live, we would undoubtedly endanger the salvation of others, either because he would corrupt the faithful whom he met, or because his escape from punishment would lead others to believe they could deny the faith with impunity. The inconstancy of the relapsed is, therefore, a sufficient reason why the Church, although she receives him to penance for his soul's salvation, refuses to free him from the death penalty.