The Thirty Third Proof that Clement of the Alexandrian See of St. Mark Was a Prominent Leader of the Tradition Irenaeus Identifies as 'Marcosian'

33. Irenaeus says the Marcosians hold that "by the fact that the length (height) of the holy tabernacle was thirty cubits and if they meet with any other like numbers, they still apply these to their Triacontad." [AH i.18.4]

Clement of Alexandria wrote that "let the testimony of geometry be the tabernacle that was constructed, and the ark that was fashioned, -- constructed in most regular proportions, and through divine ideas, by the gift of understanding, which leads us from things of sense to intellectual objects, or rather from these to holy things, and to the holy of holies. For the squares of wood indicate that the square form, producing fight angles, pervades all, and points out security. And the length of the structure was three hundred cubits, and the breadth fifty, and the height thirty; and above, the ark ends in a cubit, narrowing to a cubit from the broad base like a pyramid, the symbol of those who are purified and tested by fire. And this geometrical proportion has a place, for the transport of those holy abodes, whose differences are indicated by the differences of the numbers set down below.

And the numbers introduced are sixfold, as three hundred is six times fifty; and tenfold, as three hundred is ten times thirty; and containing one and two-thirds (epidimoiroi), for fifty is one and two-thirds of thirty.

Now there are some who say that three hundred cubits are the symbol of the Lord's sign; and fifty, of hope and of the remission given at Pentecost; and thirty, or as in some, twelve, they say points out the preaching [of the Gospel]; because the LOrd preached in His thirtieth year; and the apostles were twelve. And the structure's terminating in a cubit is the symbol of the advancement of the righteous to oneness and to "the unity of the faith." [Stromata vi.11]