D. Whether Different Sacraments Needed to be Instituted

251. About the fourth point [n.223] one must first see how sacraments can be distinguished, and secondly turn to the point at issue.

1. How Sacraments can be Distinguished

252. On the first point, note that a sacrament is distinguished in one way as a term is into its significations, namely into sacrament properly said and sacrament improperly said. It is distinguished in another way as a higher class is into its lower kinds, and this in three ways. For since it is a sensible thing signifying something, it can be different sacraments because it can be different sensible things. Or it can be a different sacrament having a different signification, and that in two ways - either a simply different signification with respect to different signified things, or a signification different in a certain respect as regard a thing that varies as to more and less.

2. Response to the Issue at Hand

253. As to the issue at hand, I say that one can find in each Law a sacrament that is distinguished in the first way. For just as in each Law there was a sacrament properly speaking (from the third article [n.246]), so there was a sacrament improperly speaking -indeed many such sacraments improperly speaking, as genuflections, bowings, or prostrations on the ground and the like, which can be called ‘sacred signs’ generally and so ‘sacraments’ improperly. These and many others too could have been the same in the Mosaic Law and the Evangelical law.

254. But when talking of a sacrament properly speaking, I say that there ought to have been different ones in each Law; and this (setting aside the other sacraments) was fitting in respect of the sacrament instituted as medicine against the sickness of original sin.

255. For this sacrament had to be different by reason of the signification and by reason of the sensible thing instituted to do the signifying.

256. The proof of the first point is not indeed that it ought to be simply different with respect simply to the other Law. For, from the fact that there was medicine in each Law against the same disease, what was signified by such sacraments was not simply different in the different Laws, but the signification of the one had to be different with respect to the other as to variation of more and less. The proof is that ‘in the development of the human race the knowledge of truth increased’, as is plain from Gregory on Ezekiel 2.4 n.12 [cf. John 16.13, ‘When the Spirit of truth comes he will teach you all truth’]. Therefore, it was fitting that in the later Law the instituted sign signified more evidently the thing signified. Now the later Law was always more perfect, because God, who acts in orderly fashion, proceeds from the imperfect to the perfect. But a more perfect Law requires more perfect aids for its observance; therefore, the later Law had to have a sacrament signifying a more perfect grace. Therefore was it thus fitting that in the different laws there was a different signification, and a more manifest one in the later Law and in respect of the signified later thing.

257. From this follows that it was fitting for there to be sacraments different as to the sensible thing that did the signifying [n.255]. For it was more fitting (as to signifying a more perfect grace and for signifying it more manifestly) that a new sign was imposed than that the old one remained. For the old one was, from its imposition, in no way able to signify anything other than what it signified at first. But to impose the original sign or original sensible thing in the second Law for signifying something other than it signified before, or for signifying in another way, was not as fitting as to impose another sign, as is plain even in the case of practical signs imposed by us. For a new sign was more reasonable for signifying the more perfect effect among us, and because to impose a new sign was more manifest than again to impose the old one (which was first imposed for something else).