While they found blood upon the departed and unharmed Israelites’ door-posts, the sorrowing Egyptians must have seen that it had been sprinkled there, not at hazard, but with the studied purpose of making therewith the Egyptian letter Tau, as it used to be fashioned at the time. But what was then its common shape? That the old Tau was a cross, we are told by written authority, and learn from monumental evidence. Learned as he was in all the wisdom of the Egyptians, Moses, no doubt, wrote with the letters of their alphabet. Now, the oldest shape of the Tau in the Hebrew alphabet, and still kept up among the Samaritans in St. Jerome’s days, was in the form of a cross: “Antiquis Hebræorum literis, quibus usque hodie Samaritæ utuntur, extrema Tau crucis habet similitudinem, quæ in Christianorum frontibus pingitur et frequentius manus inscriptione signatur.”[415] For monumental testimony we refer the reader to the proofs we have given, at large, in “Hierurgia,” pp. 352-355, second edition. Strengthening our idea that the lamb’s blood had been put on the door-post in the shape of a cross, and that hence the old Egyptians had borrowed it as a spell against evil hap, and a symbol of a life hereafter, is a passage set forth, first by Rufinus, A.D. 397, and then by Socrates, A.D. 440:--“On demolishing at Alexandria a temple dedicated to Serapis, were observed several stones sculptured with letters called hieroglyphics, which showed the figure of a cross. Certain Gentile inhabitants of the city who had lately been converted to the Christian faith, initiated in the method of interpreting these enigmatic characters, declared that the figure of the cross was considered as the symbol of future life.”[416] We know that, while the old Tau kept the shape of a cross, it took at least three modifications of that form on those monuments which, up to this time, have been brought to light: others may turn up with that letter traced exactly like the so-called “gammadion” found upon an Egyptian stuff of such an early date. Most probably this was the very shape, but with shorter arms, of the letter found traced upon the door-posts. [415] Hier. in cap. ix. Ezech. [416] Hist. Eccles. lib. v. c. 17.