Low Mass

Low Mass (called in Latin, Missa lecta, which literally means "read 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 (deacon and subdeacon); without them it is a Missa Cantata.

"Private Mass" (in Latin, Missa privata or secreta, familiaris, peculiaris), 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.

In Low Mass incense is not used and the responses (in Latin) are given by one or more servers. Low Mass, celebrated in exactly the same way whether a congregation is present or not, was the most common form of Mass before 1969. In the 1970 edition of the Roman Missal a distinction was made between Mass celebrated with a congregation and Mass celebrated without a congregation. No such distinction was made in earlier (Tridentine) editions of the Roman Missal, which only distinguished between Solemn Mass and Low Mass (calling the latter Missa lecta or, as in the Rubricae generales Missalis included in pre-1962 editions, Missa privata).

The term "Low Mass" is sometimes used also by Christians not in communion with the Holy See for a spoken, not sung, form of their own Eucharistic celebrations. However, this article concerns only the form of the Roman Rite of Mass officially known by that name.

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