Amen is a ratification of what has preceded, sometimes by the speaker himself, as in S. John v. 24, 25, vi. 53, Rom. ix. 5; sometimes by the hearers, as in Deut. xxvii. 15, &c., Psalm cvi. 48, I Cor. xiv. 16. When used at the conclusion of parts of Divine Service in which the Minister and people join aloud, as in Confessions, Creeds, the Lord's Prayer, and Doxologies, it will be said, as part of the devotion itself, by both Minister and people. When used after acts of worship in which the Minister only has spoken, as in Absolutions, Benedictions, and 'other prayers' said by the minister alone, it is an answer of the people, and therefore to be said by the people only.
In the Lord's Prayer at the beginning of the Communion Office, and in the formulae of Baptism, and of reception into the Church, it is a ratification by the speaker himself, not an answer of the people, and should not, as it seems, be said by the people also.
22. Then the Minister shall kneel, and say the Lord's Prayer with an audible voice; the people also kneeling, and repeating it with him, both here, and wheresoever else it is used in Divine Service.
The Lord's Prayer is to be repeated by the people with, not after the Minister, i.e., taking up each clause as he begins it, in the same manner as the Creed. It was ordered in 1549, 1552, and 1604, that the Priest [Minister] should begin the Lord's Prayer. This is a reason for the practice of the Priest saying the first two words alone.
23. Then likewise he shall say, O Lord, open, &c.
24. Here all standing up, the Priest shall say, Glory be, &c.
The posture of standing, here directed, is to be continued through the Venite and Psalms. It is a devout usage to turn to the East at the Gloria Patri. (See ante p. 12, note d.)
It is also an old custom in some places to bow.
25. Then shall be said or sung this Psalm following: except on Easter-Day, upon which another Anthem is appointed; and on the Nineteenth day of every Month it is not to be read here, but in the ordinary Course of the Psalms. O come, let us sing, &c.
With regard to Easter Day, it is to be noticed that the "other anthem" provided for that day is intended to be used on that day only and not during the Octave, in accordance with the ancient precedent, of using on Easter Day only the short Introductory Office in which the central part and foundation of the Anthem (viz., 'Christ being raised,' &c.) occurred. If it be desired, therefore, to use this group of Anthems during the remainder of Easter Week, it must be sung as an Anthem after the third collect, but it should not be substituted for the Venite.