25. The _sambuca_ or staff, with which the alphabet is written, showeth the doctrine of the apostles, or the mystery of the teachers, by which the conversion of the Gentiles hath been effected, and the perfidy of the Jews. Afterwards approaching the altar the bishop standeth, and beginneth by saying, 'O God, make speed to save us;' because he is then beginning the principal part of office. And the versicle, 'Glory be to the Father,' etc., is then said. 26. Because this benediction is used to set forth the glory of the Trinity, Alleluia is not then uttered, as will be set forth in the next chapter. Then the bishop consecrateth the altar, for which he blesseth other water, as {101} shall also be declared in the next chapter. With which water also, after that the altar hath been sprinkled seven times, the whole interior of the church is sprinkled three times, as at first without any distinction between greater and smaller stones, since 'there is no respect of persons with God.' For this reason is the interior sprinkled, to signify that an external ablution profiteth nothing without an internal charity. And for this reason three times, because, as hath been premised, that aspersion signifieth the aspersion and cleansing of baptism, which is conferred through the invocation of the Trinity, according to the saying, 'Go ye and teach all nations, baptising them in the name of the Father, and of the Son, and of the Holy Ghost:' [Footnote 398] for since a church cannot be immersed in water as a man in baptism is immersed, it is on this account sprinkled three times with water, as if in the place of a threefold immersion. [Footnote 398: S. Matt, xxviii, 19.] 27. Again, the bishop performeth the aspersion proceeding from the east to the west and once through the middle in the form of the cross; because Christ gave instructions to baptise the whole of Judea and all nations in the name of the Trinity, to which baptism He gave efficacy in the ministry of His Passion, beginning from the Jews, from whom He had His birth. And what remains of the water is poured away at the foot of the altar, as shall be mentioned in the next chapter. Some, however, do not bless any fresh water, but perform the whole office with that which was blessed at first. In the meanwhile, however, the choir is chanting the Psalm _Exsurgat Deus_ ('let God arise and let His enemies be scattered,' etc.), and the _Qui habitat_ ('whoso dwelleth,' etc.), in which mention is made of the church and its consecration, as is plain in that verse, 'He is the God {102} that maketh 'men to be of one mind in an house.' [Footnote 399] But the bishop saith, 'My house shall be called an house of prayer,' because it is his duty to cause that the church should be a house of God, not of merchandise. [Footnote 399: Psalm lxviii (_Exsurgat Deus_), v, 5.]