It is remarkable that in Cyril’s account of the Eucharistic rites in this Lecture there is not the slightest reference to the words of Institution, though these hold so prominent a place before the Invocation both in the Clementine Liturgy and in the Liturgy of S. James.  But we cannot justly assume, from a mere omission in so brief a summary, that the Commemoration of the Institution had no place in the Liturgy then in use at Jerusalem.  It seems more probable that Cyril did not think it necessary, after his repeated references to the Institution in the preceding Lecture, to make further mention of a custom so well known as the recitation of Christ’s own words in the course of the Prayer preceding the Invocation.  On the previous day he had quoted S. Paul’s account of the Institution, with the remark, “Since then He Himself has declared and said of the Bread, This is My Body, who shall dare doubt any longer?  And since He has Himself affirmed and said, This is My Blood, who shall ever hesitate, saying that it is not His Blood Mystag. iv. § 1.?”  The like efficacy he again ascribes to “the Lord’s declaration” concerning both the Bread and the Wine, that they are “the Body and Blood of Christ Ib. § 6:  see also § 7..”