Deo Gratias
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Cyclopedia of Biblical, Theological and Ecclesiastical Literature [1]
(Thanks be to God), a response of the people in the liturgy: derived from the apostolic use of the phrase ( 1 Corinthians 15:57; 2 Corinthians 2:14). According to the Mozarabic rite the people said "Deo gratias" at the naming of the passage to be read as the "prophecy" in the liturgy. Bona speaks of it being used instead of "Amen," or "Laus tibi Christe," when the gospel was ended. Augustine notices it as a common mode of greeting among the monks, for which they were ridiculed by the Agonistici among the Donatists. It was sometimes used by way of acclamation on other occasions.
