Reciprocal proof does not make the Church better known than Scripture
However good and valid an argument may be drawn from the Church's consensus and testimony to prove a sacred book's divinity, we deny that Scripture's authority therefore depends on the Church's as on something better known and superior.
We can force this even from unwilling adversaries. Just as the Fathers answered heretics who denied Scripture from the Church's authority and testimony, they also sent schismatics who would not own Christ's true Church back to the Scriptures, and held that the true Church must be shown from them.
So Augustine with the Donatists: whether they hold the Church, let them show it only by the canonical books of the divine Scriptures. Today the Pontificians try to prove their Church and its authority from Scripture, and think they do that office well.
Yet they refuse to allow that, for us, the Church's authority is less known and certain than Scripture's — which is exactly the point under inquiry: we affirm it; they deny it.
So from the fact that a disputed book of Scripture has no fitter or surer defense against heretics than the Church's consensus and testimony, they cannot conclude that the Church's authority is for us more certain and better known than Scripture's.
They themselves must admit that a heretic who does not acknowledge the true Church cannot be answered by any firmer argument than Scripture's authority — and yet they most of all shrink from saying that sacred Scripture's authority is for us prior to and better known than the Church's.
Latin
XLII. Sed quantumvis bonum & validum argumentum sumi possit ex Ecclesiae consensu & testimonio pro libri alicujus sacri divinitate comprobanda, negamus inde sequi authoritatem Scripturae ab authoritate Ecclesiae pendere tanquam notiori & superiori. Quod ab ipsis adversariis vel maxime invitis extorquere possumus. Nam quemadmodum Patres refellerunt haereticos qui Scripturam negabant ex authoritate & testimonio Ecclesiae; ita quoque Schismaticos veram Ecclesiam Christi non agnoscentes ad Scripturas revocarunt, & ex iis veram Ecclesiam demonstrandam esse contenderunt. Sic enim Augustinus cum Donatistis agit, utrum ipsi Ecclesiam teneant nonnisi divinarum Scripturarum Canonicis libris ostendant. Et hodie Pontificii Ecclesiam suam, & ejus authoritatem ex Scripturis probare conantur: Et eo se officio egregie defungi putant. Et tamen minime volunt Ecclesiae authoritatem quoad nos minus notam & certam esse Scripturae authoritate: quod est ipsum de quo hic quaeritur, & quod affirmamus, illi vero negant. Igitur ex eo quod Scripturae liber aliquis in dubium vocatus, non potest aptiori & certiori argumento contra haereticos defendi, quam ex Ecclesiae consensu & testimonio, Pontificii concludere non possunt authoritatem Ecclesiae certiorem quoad nos & notiorem esse Scripturae authoritate: quandoquidem fateri coguntur haereticum, qui veram Ecclesiam non agnoscit, non posse certiori & firmiori argumento revinci quam Scripturae authoritate. Et tamen ab eo maxime abhorrent ut dicant Scripturae sacrae authoritatem quoad nos authoritate Ecclesiae priorem & notiorem esse.