Calvin on the (lack of) rhetoric in scripture

Why read John Calvin’s Institutes of the Christian Religion? For gems like this:

In vain were the authority of Scripture fortified by argument, or supported by the consent of the Church, or confirmed by any other helps, if unaccompanied by an assurance higher and stronger than human judgement can give. Till this better foundation has been laid, the authority of Scripture remains in suspense. On the other hand, when recognising its exemption from the common rule, we receive it reverently, and according to its dignity, those proofs which were not so strong as to produce and rivet a full conviction in our minds, become most appropriate helps. For it is wonderful how much we are confirmed in our belief, when we more attentively consider how admirably the system of divine wisdom contained in itis arranged – how perfectly free the doctrine is from every thing that savours of earth – how beautifully it harmonises in all its parts – and how rich it is in all the other qualities which give an air of majesty to composition. Our hearts are still more firmly assured when we reflect that our admiration is elicited more by the dignity of the matter than by the graces of style. For it was not without an admirable arrangement of Providence, that the sublime mysteries of the kingdom of heaven have for the greater part been delivered with a contemptible meanness of words. Had they been adorned with a more splendid eloquence, the wicked might have cavilled, and alleged that this constituted all their force. But now, when an unpolished simplicity, almost bordering on rudeness, makes a deeper impression than the loftiest flights of oratory, what does it indicate if not that the Holy Scriptures are too mighty in the power of truth to need the rhetorician’s art?