Institutes of Elenctic Theology by Francis Turretin

The passage of Augustine, 'I would not believe the gospel if the authority of the church did not move me' (Against the Epistle of Manichaeus Called Fundamental 5 [NPNF1, 4:131; PL 42.176]) does not favor the papists. First, Augustine speaks of himself as still a Manichean and not yet a Christian. What he places in the imperfect is equivalent to the preterite pluperfect: 'I would believe and it would move' for 'I would have believed and it would have moved''a very common usage with the Africans (as the learned observe); cf. Augustine, 'If I would then love that fruit' for 'I would have loved' (Confessions 2.8 [FC 21:46; PL 32.682]).Second, the authority of which he speaks is not that of right and power (which our opponents here pretend), as if he would have believed because the church so ordered; but that of worth, derived from the great and remarkable proofs of the providence of God (visible in the church) such as miracles, the agreement of people, the succession, etc. (Augustine, Against the Epistle of Manichaeus Called Fundamental 4 [NPNF1, 4:130]) whichcan lead to faith, although unable to produce it primarily. Third, the external motive to faith is here alluded to and not the infallible principle of believing which chap. 4 teaches us is to be sought in the truth alone. For heacknowledges that truth is to be preferred before everything else, if it is so perfectly exhibited as that it cannot be called into question.

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