14 Omitting therefore many passages in these Books where Christ may be found, but which require longer explanation and proof, although the most hidden meanings are the sweetest, convincing testimony may be obtained from the enumeration of such things as the following:— That Enoch, the seventh from Adam, pleased God, and was translated, as there is to be a seventh day of rest into which all will be translated who, during the sixth day of the world's history, are created anew by the incarnate Word.
That Noah, with his family is saved by water and wood, as the family of Christ is saved by baptism, as representing the suffering of the cross. That this ark is made of beams formed in a square, as the Church is constructed of saints prepared unto every good work: for a square stands firm on any side. That the length is six times the breadth, and ten times the height, like a human body, to show that Christ appeared in a human body. That the breadth reaches to fifty cubits; as the apostle says, "Our heart is enlarged," that is, with spiritual love, of which he says again, "The love of God is shed abroad in our heart by the Holy Ghost, which is given unto us." For in the fiftieth day after His resurrection, Christ sent His Holy Spirit to enlarge the hearts of His disciples.
That it is three hundred cubits long, to make up six times fifty; as there are six periods in the history of the world during which Christ has never ceased to be preached—in five foretold by the prophets, and in the sixth proclaimed in the gospel. That it is thirty cubits high, a tenth part of the length; because Christ is our height, who in his thirtieth year gave His sanction to the doctrine of the gospel, by declaring that He came not to destroy the law, but to fulfil it. Now the ten commandments are to be the heart of the law; and so the length of the ark is ten times thirty.
Noah himself, too, was the tenth from Adam. That the beams of the ark are fastened within and without with pitch, to signify by compact union the forbearance of love, which keeps the brotherly connection from being impaired, and the bond of peace from being broken by the offenses which try the Church either from without or from within. For pitch is a glutinous substance, of great energy and force, to represent the ardor of love which, with great power of endurance, bears all things in the maintenance of spiritual communion.
Source: Reply to Faustus the Manichaean (New Advent)