Sacred art is not meant, primarily, to help people to know good things, rather it is to inspire us to do good things, through beauty.

If we were to believe what some say, especially professional art historians it seems, then the main purpose for the creation of Catholic art of the past, for example in the stained glass windows of gothic cathedrals, was to teach scripture to the illiterate. Some, might broaden this slightly and tell us that it is to teach Catholic doctrine, but again, to the illiterate. This can, in turn, be asserted by Catholics who think that it is a good thing, and occasionally, Eastern Rite Christians who criticize Catholic art for this reason and tell us that the iconographic tradition forms the hearts of those who worship, while they worship, in contrast to what the would argue are degenerate naturalistic forms. I explain why I suspect the historians are wrong and doubt that has been the main goal of Roman Catholics in the past, but even if the historians are correct, then this narrow defined didactic purpose should not have been the main purpose or Catholic sacred art, because the Roman Catholic Church has consistently told us otherwise. This posting is the second in a two-part article.

The Council of Trent, in the 16th century, did refer to art and its role as an aid to the teaching role of the Bishops, but this is only after reiterating the words of the Seventh Ecumenical Council of 785AD:

Moreover, that the images of Christ, of the Virgin Mother of God, and of the other saints, are to be had and retained particularly in temples, and that due honour and veneration are to be given them; not that any divinity, or virtue, is believed to be in them, on account of which they are to be worshipped; or that anything is to be asked of them; or, that trust is to be reposed in images, as was of old done by the Gentiles who placed their hope in idols; but because the honour which is shown them is referred to the prototypes which those images represent; in such wise that by the images which we kiss, and before which we uncover the head, and prostrate ourselves, we adore Christ; and we venerate the saints, whose similitude they bear: as, by the decrees of Councils, and especially of the second Synod of Nicaea, has been defined against the opponents of images.

(The Council of Trent, Twenty-fifth Session, On the Invocation, Veneration, and Relics, of Saints, and on Sacred mages.)

The Council then went on to advise bishops to teach:

...that, by means of the histories of the mysteries of our Redemption, portrayed by paintings or other representations, the people is instructed, and confirmed in (the habit of) remembering, and continually revolving in mind the articles of faith; as also that great profit is derived from all sacred images, not only because the people are thereby admonished of the benefits and gifts bestowed upon them by Christ, but also because the miracles which God has performed by means of the saints, and their salutary examples, are set before the eyes of the faithful; that so they may give God thanks for those things; may order their own lives and manners in imitation of the saints; and may be excited to adore and love God, and to cultivate piety. But if any one shall teach, or entertain sentiments, contrary to these decrees; let him be anathema.

This is not, it seems to me describing a simple scripture lesson for the illiterate, rather it is an additional tool at the disposal of those who are (or at least ought to be) the primary teachers of the Church. One could as easily interpret what is being described (especially light of the effect that the Council had on sacred art subsequently) as mystagogical catechesis that is directed towards orthopraxis. That is, art is there to inspire prayer and right worship, and people can be instructed on how to engage with it so that this happens when they do so.

The Council concluded its remarks on sacred art by cautioning against images that could lead the viewer away from the teachings of the Church:

And if any abuses have crept in amongst these holy and salutary observances, the holy Synod ardently desires that they be utterly abolished; in such wise that no images, (suggestive) of false doctrine, and furnishing occasion of dangerous error to the uneducated, be set up. And if at times, when expedient for the unlettered people; it happen that the facts and narratives of sacred Scripture are portrayed and represented; the people shall be taught, that not thereby is the Divinity represented, as though it could be seen by the eyes of the body, or be portrayed by colors or figures.

Moreover, in the invocation of saints, the veneration of relics, and the sacred use of images, every superstition shall be removed, all filthy lucre be abolished; finally, all lasciviousness be avoided; in such wise that figures shall not be painted or adorned with a beauty exciting to lust; nor the celebration of the saints and the visitation of relics be by any perverted into revelings and drunkenness; as if festivals are celebrated to the honor of the saints by luxury and wantonness.

Finally, let so great care and diligence be used herein by bishops, as that there be nothing seen that is disorderly, or that is unbecomingly or confusedly arranged, nothing that is profane, nothing indecorous, seeing that holiness becometh the house of God. And that these things may be the more faithfully observed, the holy Synod ordains, that no one be allowed to place, or cause to be placed, any unusual image, in any place, or church, howsoever exempted, except that image have been approved of by the bishop.

More recently, in the 20th century the constitution of the Vatican II, Sacrosanctum Concilium (SC 127) suggests the following:

All artists who, prompted by their talents, desire to serve God's glory in holy Church, should ever bear in mind that they are engaged in a kind of sacred imitation of God the Creator, and are concerned with works destined to be used in Catholic worship, to edify the faithful, and to foster their piety and their religious formation.

A formation can include the imparting of information and knowledge of scripture, but a religious formation is, as stated before, primarily directed to the end of guiding us to right worship.

The Catechism of the Catholic Church is similar (CCC 2502):

Sacred art is true and beautiful when its form corresponds to its particular vocation: evoking and glorifying, in faith and adoration, the transcendent mystery of God—the surpassing invisible beauty of truth and love visible in Christ, who "reflects the glory of God and bears the very stamp of his nature," in whom "the whole fullness of deity dwells bodily." This spiritual beauty of God is reflected in the most holy Virgin Mother of God, the angels, and saints. Genuine sacred art draws man to adoration, to prayer, and to the love of God, Creator and Savior, the Holy One and Sanctifier.

As we know, Catholics do not always follow the guidance of Mother Church! If the art historians are right and the role of art has been primarily a narrow didactic role, then it means that consistently and through centuries, artists have been ignorant of, deliberately ignoring, or at least unable to fulfill what the Church has been telling them about sacred art.
There is another point to make, in regard to the recent period in Church history. Since at least the beginning of the 19th-century, in my opinion, the art created by Catholic artists began to decline in quality and, generally speaking, failed more and more in its purpose of ‘drawing man to adoration, prayer, and the love of God’. (I have made the argument in other articles on this blog, as to how and why stylistic changes in this period led to this decline, and more generally to a decline in Catholic culture). This, it occurs to me might explain why there is a focus today on the didactic purpose of sacred art, for if it fails to inspire through beauty then that is all you have. Furthermore, if it lacks divine beauty then ultimately it will fail in this lesser purpose as well for people will not be so inclined to look at it. So much of the art was there to no real purpose. This being so, it would not only explain but even justify in the minds of those who were responsible, the iconoclasm in a period in the 20th century US Catholic Church! The right response, I would argue, is to try to inspire and form artists to create better, more beautiful art which participates in the traditional forms of Catholic sacred art.