From the Catena Aurea of St. Thomas Aquinas, a collection of patristic quotes making up a running commentary of the Gospels, the following commented upon the tearing of the veil:
Aug., de Cons. Ev., iii, 19: The wording sufficiently shews that the veil was rent just when He gave up the ghost. If he had not added, “And, lo!” but had merely said, "And the veil of the temple was rent,: it would have been uncertain whether Matthew and Mark had not inserted it here out of its place as they recollected, and Luke had observed the right order, who having said, “And the sun was darkened,” adds, “And the veil of the temple was rent in twain;” [Luke 23:45] or, on the contrary, Luke had returned to what they had inserted in its place.
Origen: It is understood that there were two veils; one veiling the Holy of Holies, the other, the outer part of the tabernacle or temple. In the Passion then of our Lord and Saviour, it was the outer veil which was rent from the top to the bottom, that by the rending of the veil from the beginning to the end of the world, the mysteries might be published which had been hid with good reason until the Lord’s coming. “But when that which is perfect is come,” [1 Cor 13:10] then the second veil also shall be taken away, that we may see the things that are hidden within, to wit, the true Ark of the Testament, and behold the Cherubim and the rest in their real nature.
HILARY; Or, The veil of the temple is rent, because from this time the nation was dispersed, and the honour of the veil is taken away with the guardianship of the protecting Angel.