Low Mass
Low Mass is a Tridentine Mass defined officially in the Code of Rubrics included in the 1962 edition of the Roman Missal as Mass in which the priest does not chant the parts that the rubrics assign to him. A sung Mass in turn is a Solemn or High Mass if celebrated with the assistance of sacred ministers; without them it is a Missa Cantata. "
Private Mass", which is now understood as Mass celebrated without a congregation, formerly meant any Low Mass, even with a large congregation. In editions of the Roman Missal earlier than that of 1962, "Missa privata" was still contrasted with "Missa solemnis". In 1960 Pope John XXIII, who in 1962 removed from the Roman Missal the section headed
Rubricae generales Missalis, replacing it with his Code of Rubrics, decried use of the term "Missa privata": "The most sacred Sacrifice of the Mass celebrated according to the rites and regulations is an act of public worship offered to God in the name of Christ and the Church. Therefore, the term 'private Mass' should be avoided." When applied to Low Mass in general, the word
privata indicated that that form of Mass was
deprived of certain ceremonies.