The Christian's relation to images according To John Calvin

I am not, however, so superstitious as to think that all visible representations of every kind are unlawful. But as sculpture and painting are gifts of God, what I insist for is, that both shall be used purely and lawfully, - that gifts which the Lord has bestowed upon us, for his glory and our good, shall not be preposterously abused, nay, shall not be perverted to our destruction.

We think it unlawful to give a visible shape to God, because God himself has forbidden it, and because it cannot be done without, in some degree, tarnishing his glory. And lest any should think that we are singular in this opinion, those acquainted with the productions of sound divines will find that they have always disapproved of it. If it be unlawful to make any corporeal representation of God, still more unlawful must it be to worship such a representation instead of God, or to worship God in it. The only things, therefore, which ought to be painted or sculptured, are things which can be presented to the eye; the majesty of God, which is far beyond the reach of any eye, must not be dishonored by unbecoming representations. [....]

But [...] let us here consider, whether it is expedient that churches should contain representations of any kind, whether of events or human forms. First, then, if we attach any weight to the authority of the ancient Church, let us remember, that for five hundred years, during which religion was in a more prosperous condition, and a purer doctrine flourished, Christian churches were completely free from visible representations. Hence their first admission as an ornament to churches took place after the purity of the ministry had somewhat degenerated. I will not dispute as to the rationality of the grounds on which the first introduction of them proceeded, but if you compare the two periods, you will find that the latter had greatly declined from the purity of the times when images were unknown. What then? Are we to suppose that those holy fathers, if they had judged the thing to be useful and salutary, would have allowed the Church to be so long without it? Undoubtedly, because they saw very little or no advantage, and the greatest danger in it, they rather rejected it intentionally and on rational grounds, than omitted it through ignorance or carelessness. [...] This undoubtedly is the reason why John (1 John 5: 21) enjoins us to beware, not only of the worship of idols, but also of idols themselves. And from the fearful infatuation under which the world has hitherto laboured, almost to the entire destruction of piety, we know too well from experience that the moment images appear in churches, idolatry has as it were raised its banner; because the folly of manhood cannot moderate itself, but forthwith falls away to superstitious worship. Even were the danger less imminent, still, when I consider the proper end for which churches are erected, it appears to me more unbecoming their sacredness than I well can tell, to admit any other images than those living symbols which the Lord has consecrated by his own word: I mean Baptism and the Lord's Supper [...].

Source: Institutes of the Christian Religion John Calvin, Book I, chap. 11, § 12-13

A New Translation by Henry Beveridge, Esq. Volume First. Edinburgh: Printed for the Calvin Translation Society

Calvin worked at his Institutes of the Christian Religion (a title which could be translated today by “Christian Teaching”) for a quarter of a century; they went through a range of publications in Latin and in French. Beveridge's translation dates back to 1845