VII. Immortality of the soul defined; Bernard, Nyssenus, Augustine, Ambrose on death as change
VII. The immortality of the soul is that perfection of it by which, without destruction of its substance, by the kindness of its Creator, it endures forever.
This is opposed to death strictly taken, inasmuch as it is extinction with respect to the destruction of substance. Otherwise certain of the fathers take death more loosely, for change with respect to its state, whatever that finally is. So Bernard: Every change, he says, is a death. And therefore Nyssenus proves that death is implicated in this life, because this life is subject to change.
Augustine agrees in book 3 against Maximinus the Arian bishop, chapter 12, column 730: Immortality, he says, God alone is said to have, because he alone is immutable. For in every changeable nature the change itself is some death, because it makes something in it not to be what it was. Accordingly the human soul itself, which is therefore called immortal because in whatever way, according to its own mode, it never ceases to live, nevertheless has according to that same mode a certain death of its own: because if it was living justly and sins, it dies to justice; if it was a sinner and is justified, it dies to sin — not to mention its other changes, about which it is long to dispute.
Ambrose agrees in book 3 On faith, chapter 2: And the soul, he says, dies. For the soul that has sinned, it itself shall die. Every rational creature receives accidents and is subject to judgment. But in accidents both the penalty of judgment is corruption and also progress.
Latin
VII. Immortalitas animae est illius perfectio, qua sine substantiae suae destructione, benignitate creatoris sui in aeternum, durat. Haec opponitur morti stricte sumtae, quatenus est exstinctio, quod ad substantiae destructionem. Ex patribus alioquin quidam mortem laxius accipiunt, pro mutatione quod ad taliter esse, quae demum illa cunque sit. Sic Bernhardus: Omnis, inquit, mutatio mors est. Et ideo Nyssenus probat huic vitae mortem implicatam esse, quod mutationi ista vita subjecta sit. Consentit Augustinus lib. 3. contra Maximinum Arianorum episcopum cap. 12. col. 730. Immortalitatem, inquiens, Deus habere dicitur solus, quia est immutabilis solus. In omni enim mutabili natura nonnulla mors est ipsa mutatio, quia facit aliquid in ea non esse quod erat. Proinde & ipsa anima humana, quae propterea dicitur immortalis, quoniam qualitercunque, secundum modum suum nunquam desinit vivere: habet tamen pro ipso suo modo quandam mortem suam: quia, si juste vivebat & peccat, moritur justitiae: si peccatrix erat & justificatur, moritur peccato: ut alias ejus mutationes taceam, de quibus longum est disputare. Consentit Ambrosius lib. 3. de fide cap. 2. Et anima, inquiens, moritur. Anima enim quae peccaverit, ipsa morietur. Omnis rationabilis creatura accidentia recipit & subjecta judicio est. In accidentibus autem & poena judicii corruptela est & profectus.