Amen
a Hebrew word of asseveration, equivalent to "Yea," "Truly," which has been commonly adopted in the forms of Christian worship. In Jewish synagogues, the "Amen" is pronounced by the congregation at the conclusion of the benediction given at parting. Among the early Christians, the prayer offered by the presbyter was concluded by the word "Amen," uttered by the whole congregation (cf. I Cor. xiv: 16). According to Tertullian, none but the faithful were permitted to join in the response.
In the Greek Church, this word was pronounced after the name of each person of the Trinity; and, at the close of the baptismal formula, the people responded.
At the conclusion of prayer, it signifies (according to the English Church Cathechism) "So be it"; after the repetition of the creed, "So is it." The Roman Catholic version of the New Testament (Rheims 1582), substitutes "Amen" for the "Verily" of our authorized version, it being the word used in the original Greek. The Mohammedans also use this word in their service.