The Purpose of the Blessings of the Church

[Michael Wilson]

On another thread, a poster questioned the purpose of why the Church blessed objects such as pictures, medals etc. I thought that this article in the Catholic Encyclopedia (1913) is a good explanation:
I didn't post the whole article, but for those who don't want to read this, here is a summary:
1. After the fall of our First Parents, all of material creation, came under the influence of the devil; and making them his ready instruments for the perpetration of iniquity.
2.Therefore the Church is anxious to rescue the things that we use for our daily life and in particular for the use in Religion, from this evil influence, and endowed with a potential for good.
3. Through the blessing of the Church, particularly and indulgenced blessing, religious articles such as Rosaries, scapulars, medals,Holy Pictures, Crucifixes, etc; one can gain an indulgence from their pius use.
4."Invocative" blessings, bring a spiritual or temporal good upon a person or object, without changing their nature, such as the blessing of our food, of people etc.
5. "Constituitive" blessings, change the character of the object, and permanently consecrate it for religious purposes, such as Churches, Chalices, even persons.
6. "Intermediate",by which things are rendered special instruments of salvation without at the same time becoming irrevocably sacred, such as blessed salt, candles, etc
7.Finally, blessings and blessed objects are not sacraments, but sacramentals, that when used piusly have the effect of arousing in the user a sorrow for sin & a love of God, which obtains a remission of their Venial sins and God's blessing etc.   
   
https://www.newadvent.org/cathen/02599b.htm

Objects
The range of objects that come under the influence of the Church's blessing is as comprehensive as the spiritual and temporal interests of her children. All the lower creatures have been made to serve man and minister to his needs. As nothing, then, should be left undone to enhance their utility towards this end, they are placed in a way under the direct providence of "Every creature of God is good. . .", as St. Paul says "for it is sanctified by the word of God and prayer" (1 Timothy 4:4-5). There is also the reflection that the effects of the Fall extended to the inanimate objects of creation, marring in a manner the original aim of their existence and making them, in the hands of evil spirits, ready instruments for the perpetration of iniquity. In the Epistle to the Romans St. Paul describes inanimate nature, blighted by the primal curse, groaning in travail and anxiously awaiting its deliverance from bondage. "The expectation of the creature waiteth for the revelation of the Sons of God. For the creature was made subject to vanity, not willingly, but by reason of him that made it subject, in hope" (viii, 19-20). From this it will be easily seen how very reasonable is the anxiety of the Church that the things which are used in daily life and particularly in the service of religion, should be rescued from contaminating influences and endowed with a potency for good...
Blessings for things
(a) In addition to the blessings already mentioned for articles destined for altar purposes, the Roman Ritual has formulæ for blessing crosses, images of Our Lord, of the Blessed Virgin and saints, church organs, processional banners, new bells for church uses and for other purposes, dress and cinctures worn in honour of Our Lady and of other saints, monstrances, reliquaries, vessels for Holy Oils, church ornaments, clerical habits, medals, pictures, and crosses for the Stations, rosaries of all the recognized kinds, water, candles, the Trisagion of the Holy Trinity, the different scapulars of Our Lady, of Our Lord, of the Blessed Trinity, of St. Joseph, St. Michael the Archangel, and other saints. Most of the objects just enumerated, as, for instance, rosaries and scapulars, receive what is called an indulgenced blessing, that is to say, by the pious employment and use of them persons are enabled to gain an indulgence.
Efficacy
Blessings may be divided into two classes, viz: invocative and constitutive. The former are those in which the Divine benignity is invoked on persons or things, to bring down upon them some temporal or spiritual good without changing their former condition. Of this kind are the blessings given to children, and to articles of food. The latter class are so called because they permanently depute persons or things to Divine service by imparting to them some sacred character, by which they assume a new and distinct spiritual relationship. Such are the blessings given churches and chalices by their consecration. In this case a certain abiding quality of sacredness is conferred in virtue of which the persons or things blessed become inviolably sacred so that they cannot be divested of their religious character or be turned to profane uses. Again, theologians distinguish blessings of an intermediate sort, by which things are rendered special instruments of salvation without at the same time becoming irrevocably sacred, such as blessed salt, candles, etc. Blessings are not sacraments; they are not of Divine institution; they do not confer sanctifying grace; and they do not produce their effects in virtue of the rite itself, or ex opere operato. They are sacramentals and, as such, they produce the following specific effects:

• Excitation of pious emotions and affections of the heart and, by means of these,     remission of venial sin and of the temporal punishment due to it;
• Freedom from power of evil spirits;
• Preservation and restoration of bodily health.
• Various other benefits, temporal or spiritual

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