Tertullian, On the Flesh of Christ 11
We run into another line of theirs, demanding why Christ, by taking on animal flesh, appears to have possessed a carnal soul. They claim God wanted to display a visible soul to human beings by turning it into a body—one that had previously been invisible, a nonentity by nature, unable even to see itself because this flesh got in the way, so that people could even argue over whether the soul was born or not, mortal or not. So the soul was made a body in Christ, letting us watch it being born, dying, and—more than that—rising again. But what kind of maneuver was this, that the soul should be demonstrated to itself or to us through flesh, when through flesh it could not be recognized? The idea is that the soul would be shown precisely while the very thing hiding it—that is, flesh—was being put on; it received darkness so it could shine.
Let us pull back once more and ask whether the soul ought to be shown in this way at all, or whether they will insist it was entirely invisible before—whether it is like something incorporeal, or whether it also has some kind of body of its own. Yet when they call it invisible, they simultaneously make it corporeal by giving it something that is invisible. Nothing that possesses an invisible element can be called invisible; indeed, it cannot even exist unless it has something through which it exists. Once it exists, it must have something through which it is. If it has something through which it is, that something is its body. Everything that exists is a body of its own kind; nothing is incorporeal except what does not exist. Since the soul therefore has an invisible body, the One who undertook to make it visible would far more fittingly have made visible that which was regarded as invisible, because neither falsehood nor weakness belongs to God: falsehood, if He demonstrated the soul to be other than what it was; weakness, if He was unable to demonstrate what it was. No one who wants to show a man puts a helmet or a mask on him. But that is exactly what was done to the soul if, once converted into flesh, it put on an alien appearance.
Even if the soul is reckoned incorporeal—so that by some rational power it may be hidden—whatever the soul is, it is not a body. Accordingly, it was not impossible for God, and it would have been more consistent with His purpose, to demonstrate it with some new kind of body rather than this common one shared by all, already known. Otherwise He would have made the invisible soul visible for no reason—namely, to serve these very questions, for the defense of human flesh. But Christ could not appear among human beings unless He seemed human. So give Christ back His own faithfulness: the One who chose to walk as a man should also show a soul of human condition, not by making it fleshly, but by clothing it with flesh.
Latin
Sed aliam argumentationem eorum convenimus, exigentes, cur animalem carnem subeundo Christus, animam carnalem videatur habuisse. Deus enim, inquiunt, gestivit animam visibilem hominibus exhibere, faciendo eam corpus, quae retro invisibilis extiterit, natura nihil, nec semetipsam videns, prae impedimento carnis hujus, ut etiam disceptaretur, nata anima an non, mortalis ne sit, an non. Itaque animam corpus effectam in Christo, ut eam et nascentem et morientem, et, quod sit amplius, resurgentem videremus. Et hoc autem quale erat, ut per carnem demonstraretur anima sibi aut nobis, quae per carnem non poterat agnosci: ut sic ostenderetur, dum id fit, cui latebat, id est caro? tenebras videlicet accepit, ut lucere posset. Denique, adhuc prius retractemus, an isto modo ostendenda fuerit anima, an in totum invisibilem eam retro allegent; utrum quasi incorporalem, an etiam habentem aliquod genus corporis proprii. Et tamen cum invisibilem dicant, corporalem eam constituunt, habentem quod invisible sit. Nihil enim habens invisibile, quomodo potest invisibilis dici? Sed ne esse quidem potest, nisi habens per quod sit. Cum autem sit, habeat necesse est aliquid, per quod est. Si habet aliquid per quod est, hoc erit corpus ejus. Omne quod est, corpus est sui generis: nihil est incorporale, nisi quod non est. Habente igitur anima invisibile corpus, qui visibilem eam facere susceperat, utique dignius id ejus visibile fecisset, quod invisibile habebatur, quia nec hic mendacium, aut infirmitas Deo competit: mendacium, si aliud animam, quam quod erat, demonstravit; infirmitas, si id quod erat demonstrare non valuit. Nemo ostendere volens hominem, cassidem aut personam ei inducit. Hoc autem factum est animae, si in carne conversa alienam induit superficiem. Sed et si incorporalis anima deputetur, ut aliqua vi rationis occulta sit quidem anima, corpus tamen non sit, quidquid est anima; proinde impossibile Deo non erat, et proposito ejus congruentius competebat, nova aliqua corporis specie eam demonstrare, quam ista communi omnium, alterius jam notitiae; ne sine caussa visibilem ex invisibili facere gestisset animam, istis scilicet quaestionibus opportunam, per carnis in illam humanae defensionem. Sed non poterat Christus inter homines nisi homo videri. Redde igitur Christo fidem suam; ut qui homo voluerit incedere, animam quoque humanae conditionis ostenderit, non faciens eam carneam, sed induens eam carne.