As we advance up the aisle you observe lying open on the altar a large book, which is called a _Missal_, or Mass-book, because it contains the prayers said at Mass. The office of the Mass consists of selections from the Old and the New Testament, the Canon and other appropriate prayers. The Canon of the Mass never varies throughout the year, and descends to us from the first ages of the Church with scarcely the addition of a word. Nearly all the collects are also very old, many of them dating back to a period prior to the seventh century. I am acquainted with no prayers that can compare with the collects of the Missal in earnestness and vigor of language, in conciseness of style and unction of piety. It is evident that their authors were men who felt what they said and were filled with the spirit of God, despising “the persuasive words of human wisdom,” unlike so many modern prayer-composers whose rounded periods are directed rather to tickle the ears of men than to pierce the clouds. You are probably familiar with the Episcopal _Book of Common Prayer_, and have no doubt admired its beautiful simplicity of diction. But perhaps you will be surprised when I inform you that this Prayer-Book is for the most part a translation from our Missal. Let us now reverently follow the officiating Priest through the service of the Mass. You see him advance from the sacristy and stand at the foot of the altar, where he makes an humble confession of his sins to God and His saints. He then ascends the altar, and nine times the Divine clemency is invoked in the _Kyrie Eleison, Christe Eleison_. He intones the sublime doxology, _Gloria in Excelsis Deo_, sings the collects of the day, reads the Lesson or Epistle and chants the Gospel, after which the sermon is usually preached. Next he recites the Nicene Creed, which for upwards of fifteen centuries has been resounding in the churches of Christendom. Then you perceive him making the oblation of the bread and wine. He washes the tips of his fingers, reciting the words of the Psalmist: “I will wash my hands among the innocent and will encompass Thy altar, O Lord.” He is admonished, by this ceremony, to be free from the least stain, in view of the sacred act he is going to perform. The Preface and Canon follow, including the solemn words of consecration, during which the bread and wine are changed by the power of Jesus Christ into His body and blood. He proceeds with other prayers, including the best of all, the _Our Father_, as far as the Communion, when he partakes of the consecrated Bread and chalice, giving the Holy Communion afterward to such as are prepared to receive it. He continues the Mass, gives his blessing to the kneeling congregation, and concludes with the opening words of the sublime Gospel of St. John.