The Reasons for and the Dates of Replacing the Audible Recitation of the Liturgical Prayers with Secret Recitationby A. Golubtsov
At the present time all prayers of the Liturgy except the one before the Ambo are, in our practice, recited by the celebrant inaudibly or secretly ("mystikos") from the people. Instead of the complete prayers the people hear only the so-called exclamations or the endings of the prayers consisting usually of a doxology to the Holy Trinity, more often as a conclusion of a preceding statement,  or brief expressions and disjointed phrases from the middle of statements , between which there is no apparent connection. It is difficult to relate this to someone unfamiliar with the context of the prayers or who never held a service book in his hands. The liturgical practice of the first three or four centuries presented a completely opposite picture. There the audible and common recitation of the prayers was taken for granted and was considered a conditio sine qua non of liturgical worship. To illustrate this we will first: refer to the well-known passage in Justin's Apology (chapter 65) in which, on behalf of the faithful of his time, he wrote:
On finishing the prayers we greet each other with a kiss. Then bread and a cup of water and mixed wine are brought to the president of the brethren and he, taking them, sends up praise and glory to the Father of the universe through the name of the Son and of the Holy Spirit and offers thanksgiving at some length that we have been deemed worthy to receive these things from him. When he has finished the prayers and the thanksgivings, the whole congregation present assents, saying, "Amen." "Amen" in the Hebrew language means, "So be it."
That the people affirmed all the prayers and thanksgiving recited audibly by the president can be seen from a passage in a letter of Dionysius of Alexandria to Bishop Sixtus of Rome, found in Eusebius's Ecclesiastical History (Book VII, ch. 8) where he writes about an individual discovered to have been baptized by heretics but who has been in communion for some time:
Hence he prayed that he might have the benefit of this most perfect cleansing [Baptism], reception and grace which I did not dare to do saying that his long communion was sufficient for this. For one who has been in the habit of hearing thanksgiving, and repeating the Amen, and standing at the table and extending his hand to receive the sacred elements….
In one of the ancient liturgical manuscripts, the Alexandrinian Ludolfi, following the words - It is meet and right - it plainly directs the praying people to participate in the Eucharistic Canon: "Then they recite (dicunt) the Eucharistic prayer, following the preceding one by the bishop (episcopum praeeuntem sequendo). 
In the above-mentioned monument the prayers are brief and their verbatim repetition would not present any difficulties and did not take up any lengthy time. But with the expansion of the text of the Liturgy which, by the 3rd-4th centuries became considerable, the reading of all prayers aloud would have been time-consuming and the attention span of those present was no longer what it had been earlier. It became necessary to replace the recitations with singing thus shortening the duration of the Service, allowing the priest to read the prayers inaudibly [secretly] at the same time when the deacon and the people would carry out parallel parts of the Service. The present symmetrical arrangement of the litanies and the protracted singing of certain hymns while the celebrant would inaudibly read the prayers prescribed in the service book, apparently were formed under the influence of today's practice. The Church's Ustav directs the deacon to coordinate his exclamations with the priest's action at the altar. A remarkable instruction concerning this has been preserved in some ancient Greek and Slavonic diatactics of Chrysostom's Liturgy. At the end of the litany, following the petition - Help us, save us, have mercy on us… there is a note: "Having said this, the deacon looks towards the priest and when he sees that the priest has finished the prayer, he then says: Wisdom" 
The Disciplina arcana has not been without influence upon the replacement of the audible reading of the liturgical prayers by the inaudible. Its basic premise, the shielding of the mysteries of faith and divine services from those not initiated in the mysteries, was perceived and applied in different ways at various times by members of the Christian communities. When the institution of the catechumenate fell away in the Church, that system evolved into a new form and found a new application for itself. As a result there arose a strict division between the celebrants of the Mysteries and the people, between the clergy and ordinary Church members. The first assumed a higher status, a special illumination by the Holy Spirit, an overall greater degree of spiritual understanding and as such they were called to an incomparably greater participation in the mysteries of faith. The rest of the members, not having been initiated into the higher mysteries were, in a significant way, deprived of such participation and were to be shielded from the mystery because of their status. As soon as this became the norm, the priest became responsible for the numerous and the most important prayers which he was required to recite secretly from the people since he alone was worthy of their content.
In [Pseudo] Dionysius we read:
The ecclesiastical hierarch, although in exercising his authority over those subordinate to him, making use of various sacred symbols understandable to them, nonetheless returns without change to his superior service.
This general expression of the system which established the separation between the hierarchy and the ordinary faithful with respect to Divine service and the concept of the cult, locked the priest and the bishop within the privileged boundaries whereby they alone are worthy of the Service and prayers and this left very little for the layman out of what they were previously able to see and hear during the Liturgy.
In our view, there was another source which influenced the closing-off of the Liturgical rite from the laymen. In ancient times, during the first three to four centuries, where possible all believers partook of the Sacred Mysteries along with the clergy and as sharers in the offering they participated more closely in the celebration of the Liturgy than did the Christians in later times. When the practice of the offering by the laity gradually fell away the laity began to approach the Eucharist less and less frequently.
It is easy to see the result of what followed the replacement of the audible prayers by inaudible ones. The Liturgical service came to be divided from what used to be a common rite, into two parallel parts: one for the people and the other, to be conducted by the clergy in the sanctuary. It is difficult to pinpoint accurately the time when the ancient Christian practice of the corporate recitation of the Liturgical prayers was finally replaced by their being read inaudibly. There is evidence to think that this change took place approximately in the Fifth century but it had its beginning earlier, as can be deduced from Canon 19 of Laodicaea, which reads that following the dismissal of the catechumens and penitents: "there should be offered the three prayers of the faithful, the first to be said entirely in silence, the second and third aloud." There have been two explanations for this. One sees this as the continuation of the ancient tradition. Another sees this as its replacement by a new order of things. In one of his sermons St John Chrysostom gives us tangible proof that in his time the Liturgy continued to preserve its earlier, completely open character and the audible reading of the Eucharistic prayers was the norm:
But there are occasions in which there is no difference at all between the priest and those under him; for instance, when we are to partake of the awful mysteries; for we are all alike counted worthy of the same things: not as under the Old Testament [when] the priest ate some things and those under him others, and it was not lawful for the people to partake of those things whereof the priest partook. But not so now, but before all one body is set and one cup. And in the prayers also, one may observe the people contributing much. For in behalf of the possessed, in behalf of those under penance, the prayers are made in common both by the priest and by them; and all say one prayer, the prayer replete with pity. Again when we exclude from the holy precincts those who are unable to partake of the holy table, it behoves that another prayer be offered, and we all alike fall upon the ground, and all alike rise up. Again, in the most awful mysteries themselves, the priest prays for the people and the people also pray for the priest; for the words, "with thy spirit," are nothing else than this. The offering of thanksgiving again is common: for neither does he give thanks alone, but also all the people. For having first taken their voices, next when they assent that it is "meet and right so to do," then he begins the thanksgiving. And why marvellest thou that the people any where utter aught with the priest, when indeed even with the very Cherubim, and the powers above, they send up in common those sacred hymns? Now I have said all this in order that each one of the laity also may be wary, that we may understand that we are all one body, having such difference amongst ourselves as members with members; and may not throw the whole upon the priests but ourselves also so care for the whole church as for a body common to us. 
In these words Chrysostom shows the liturgical practice of his time which has not departed from the examples of ancient Christian antiquity.
Emperor Justinian's 137th Novella brings us to the new conditions of ecclesiastical discipline by pointing to change of the earlier ancient practice of audible reading of the Eucharistic prayers still adhered to at the time of Chrysostom.
We order that all bishops and presbyters would perform the Divine Offering and the prayers proper to baptism, not in secret (non in secreto), but with such a voice which would be heard well by the faithful people (sed cum ea voce, quae a fidelissimo populo exaudiatur) so that the souls of the hearers would be brought to a greater piety, praise and blessing, because of them.
Although the imperial order cited Apostolic authority, (I Corinthians 14:16-17; Romans 10:10), it was unable to change or correct anything nor put a stop to the direction in the performance of Divine services. The new practice, although not as yet universal, became deeply rooted and had strong supporters. John Moschus, in his Spiritual Meadow, which was contemporary with Justinian's directive, describes both practices:
Since in some places where priests were accustomed to read the prayers aloud, little children who were present at the sacred assemblies and who were standing close by, heard and memorized these prayers. Then, in their childish play, they decided to repeat the prayers and gestures of the Liturgical service, appointing one of their kind to act as a priest, two to be deacons, then playfully placed some bread on a stone and poured some wine into a clay pot. When everything was done in accordance with the church's rite then, before the bread was broken in pieces, a flaming bolt descended from heaven and destroyed everything there, leaving not a trace of the stone or the offering. 
One can imagine that this tale, which is evidence that the audible reading of the Eucharistic prayers occurred in some places at the end of the 6th and the beginning of the 7th centuries, as related by the author of the Spiritual Meadow served to encourage the practice of inaudible reading of the prayers, since the profanation of these prayers by the children pointed to the undesirability of continuing the former practice. By the time of Patriarch Germanos (715-732) of Constantinople the inaudible reading of the prayers became the general rule. Out of all the Liturgical prayers, only the one before the ambo was read audibly and thus stood out from the others as an exception to the general rule. In Patriarch Germanos' opinion, it served as a summary of all that which was hidden from the people in the priest's inaudible prayers and thus served as a response to the justified perplexing questions from those who did not find sufficient foundation for the inaudible reading of the prayers.
Since some of those who stand outside the sanctuary are often perplexed, arguing amongst themselves and saying: "Of what aim, thought and force are the quietly read prayers" and desiring to receive some kind of an understanding, the Divine Fathers composed (the prayer at the ambo), as a summary of everything which was asked for (during the Liturgy) and thus announcing to those who wish it [a somewhat superficial understanding of what took place]."
Traces of the ancient practice of audible reading of the prayers, their later suppression notwithstanding, can still be found in the exclamations, the general structure of Church services and in some seemingly minor and apparently incidental items. Thus for example, in our Liturgy the litanies preceding the hymn to the Cherubim, are concluded with the deacon's proclamation, "Wisdom." This expression according to its use in ancient and current liturgical practice always served to call the listeners' attention to some important action or reading. But at this point one does not find in either the ancient or current practice, anything except prayers. In our view the exclamation "Wisdom" called the listeners' attention to the prayers for the faithful which followed these litanies. Today when the latter are recited inaudibly and only the ending exclamations are heard, the primary purpose of calling the listeners' attention to the prayers by the exclamation "Wisdom" falls by the wayside. Furthermore, the use of the plural number in the context of the liturgical prayers is nothing more than a remnant of the earlier participation of the people in their recitation just as is the remnant of the ancient practice of the corporate singing, by clerics, the choir and in some places, by the people of the entrance hymn, "O Come, Let us Worship" or, at a solemn hierarchical or even an ordinary service of Vespers, the singing of "O Gladsome Light."
1. For example: For Thine is the majesty; For Thou art a good God.. For unto Thee are due all glory; For holy art Thou our God; That with us they may glorify; Always, now and ever and unto the ages of ages.
Translation Copyright ~ 2000 by Alvian N. Smirensky