A: Public prayer is offered with and on behalf of the Church. St. Thomas distinguishes between common or public prayer and individual prayer (communis, et singularis). This common or public prayer is “that which is offered to God by the ministers of the Church representing the body of the faithful” (STh., II-II q.83 a.12 resp). The New Catholic Encyclopedia distills from the tradition three criteria for public prayer: “use of an approved formula, recitation in the name of the [Church]…, and legitimate delegation” (cf. Code of Canon Law 834, §2).
When the Church invokes a saint in the public prayer—for example, during the Litany of Saints at an ordination—a member of the saints is being asked to pray on behalf of the whole Church. In fact, this is a fundamental aspect of the rite of canonization: the praying of the Litany of the Saints with the inclusion of the one being canonized. The newly canonized is thus invoked in an approved formula, in the name of the Church, and through a legitimate delegation.
Blesseds “are usually venerated with celebrations on a local level in places where they were born, where they died, [or] where their relics are preserved” (Instruction Calendaria Particularia, Sacred Congregation for Divine Worship, 25). When one is declared a blessed, he may have shrines built in his name, churches placed under his patronage, and feast days established to honor what God has done in him. Nevertheless, the papal act of beatification “is permissive, not prescriptive, and is not infallible (although no beatification has ever been rescinded).” That said, the blessed is worthy of emulation and able to “enjoy a public cult of praise,” and also a “public cult of authentic relics.”
“Venerable” is a title bestowed by the pope that recognizes the heroic virtue of the person or that the person died a martyr’s death as a result of odium fidei (hatred of the faith). While the Christian faithful may ask for the venerable’s intercession privately and even promote the cause for his canonization, the Church waits upon the Lord to confirm the person’s status through a miracle before invoking him or her in public prayer. So, while “panegyric speeches about Servants of God…are prohibited in Churches,” it would seem that such speeches may take place after the person is declared “venerable.”
A person is given the title of “Servant of God” when the cause for canonization is begun. The Congregation for the Causes of Saints is very clear that “one must also refrain, even outside of Church, from any acts which could mislead the faithful into thinking that the inquiry conducted by the Bishop into the life of the Servant of God and his virtues or martyrdom carries with it the certitude that the Servant of God will be one day canonized.”
The public cult of Saint Teresa of Calcutta has been “formally extended to the universal Church. The feast of Blessed Solanus Casey (July 30), on the other hand, may only be celebrated in the Archdiocese of Detroit, his religious community, and a few other dioceses where part of his pastoral work took place. The Venerable Augustus Tolton may not have a public cult directed to him, though he may be publicly lifted up as an example to emulate, and people may pray for his intercession and canonization privately. The cause for the canonization of the Servant of God, Dorothy Day, is still underway and so there is, as of yet, no declaration of her as “Venerable.” Therefore, while the Servant of God might be known for her holiness, the Church patiently waits for the process of inquiry to take its course.
 K.J. Healy, “Prayer (Theology of),” in New Catholic Encyclopedia, 2nd ed., 14 vols. (Detroit: Thomson Gale, 2003), 11:600.
 Dom Basil Watkins, ed., The Book of Saints: A Comprehensive Biographical Dictionary (New York: Bloomsbury T&T Clark: An Imprint of Bloomsbury Publishing Plc, 2016), 785.
 P. Molinari and G.B. O’Donnell, “Canonization of Saints (History and Procedure),” in New Catholic Encyclopedia, 2nd ed., 14 vols. (Detroit: Thomson Gale, 2003), 3:61–66, at 65.
 Congregation for the Causes of Saints, Norms to be Observed in Inquiries Made by Bishops in the Causes of Saints (07 February 1983), no. 36.