These words are often used in ancient Liturgies, as well as in ours, and are an Excitation to prayer, to call back our wandring and recollect our scattered thoughts, and to awaken our Devotion, bidding us mind what we are about, namely, now when we are about to pray; to pray indeed, that is, heartily and earnestly. The Deacon in ancient Services was wont to call upon the people often ektenwV dehqwmen. Let us pray vehemently; nay, ekteneseron, still more vehemently, and the same vehementy and earnest devotion which the manner of these old Liturgies breathed, does our Church in her Liturgy call for, in these words, Let us pray; that is, with all the earnestness and vehemency that we may, that our prayers may be such as S. Iames speaks of, active, lively spirited prayers, for these are they that avail much with God. And there is none of us but must think it needful thus to be call'd upon and awakened; for thoughts will be wandring, and devotions will abate and scarce hold out to the prayers end, though it be a short one; that well said the old Hermit, (whom Melanc. mentions in his discourse de Crat.) There is nothing harder than to pray.
These words, Let us pray; as they are an Incitation to prayer in general, so they may seem to be sometimes an Invitation to another Form of petitioning, as in the Litany and other places: it being as much as to say, Let us collect our alternate supplications by Versicles and Answers into Collects or Prayers. In the Latin Liturgies (their Rubricks especially) Preces and Orationes seem to be thus distinguished, that Preces or Supplications were those alternate Petitions, where the people answered by responsive Versicles; Oratio, or prayer was that which was said by the Priest alone, the people only answering, Amen.