«GLORY TO THE FATHER» (GLORIA PATRI). — A formula of praise and glorification addressed to all three Divine Persons, it is a simple development of the Trinitarian baptismal formula (Mt. 28:19). Neither its author nor the time of its introduction into the liturgy can be precisely determined.
The doxology was used by the Fathers in various forms: that of «Glory to the Father through the Son in the Holy Spirit», almost universally in the East (Origen, De orat., 33), or that of «Glory to the Father with the Son and the Holy Spirit» (Martyrium Polycarpi, 14, 3; 22, 3). Finally, as a watchword of the Orthodox, the formula was changed to «Glory to the Father and to the Son and to the Holy Spirit» (Syriac inscription of 369; Flavian of Antioch, c. 381), while the Arians held to the first form, «Glory to the Father through the Son in the Holy Spirit», which in itself was not erroneous but was misinterpreted by them (St Basil, De Spiritu Sancto, 375). In the Mozarabic liturgy, according to Ps. 28:2, it is said as «Glory and honour to the Father and to the Son and to the Holy Spirit», as per the Fourth Council of Toledo, canon XV (633), attributed to St Isidore.
To the doxology was added the final clause «in saecula saeculorum. Amen», which was customary among the Jews (cf. Rom. 16:27; Heb. 13:21); it is still used today, alone, in the Mozarabic liturgy. The Greeks and Latins allow «Et nunc et semper et». Proper only to the Western Churches (excluding Spain), the clause begins with «Sicut erat in principio», introduced in the 5th century, also as a protest against the Arians, according to the first attestation at the Council of Vaison (529); it is uncertain what its subject is, whether the term «Glory» or the Son or an implied subject.
The doxology «Glory to the Father» is used as a psalm verse at the end of the psalms in the Office, except during Holy Week; in the Mass only for the psalms Indica (42) of the Introit and that of the Lavabo (25), also here except during Passiontide and Requiem Masses. The addition gives every psalm a Christian intonation; it may perhaps have been first used in Antioch in antiphonal singing and spread with it throughout the world; by the time of St Benedict its use was general. In extra-liturgical usage, the «Glory to the Father» has always been one of the most popular formulas; the first part is considered a profession of faith, sometimes accompanied by the sign of the Cross.