So also the smiting of the rock, so that the water came forth abundantly, was adopted as the sign of the giving forth of the living water springing up into everlasting life. "The rock was Christ," said St. Paul, and it is possible, that, with a secondary interpretation, the smiting of the rock was sometimes regarded as typical of the sufferings of the Saviour. The picture of this miracle is repeated again and again, and one of the noblest figures in the whole range of subterranean Art, a figure of surpassing dignity and grandeur, is that of Moses in this sublime scene in one of the chapels of the Cemetery of St. Agnes. In the performance of this miracle, Moses is represented with a rod in his hand; and a similar rod, apparently as the sign of power, is seen in the hands of Christ, in the paintings which represent his miracles. It is a curious illustration of the gradual progress of the ideas now current in the Roman Church, that upon sarcophagi of the fourth and fifth centuries St. Peter is found sculptured with the same rod in his hands,--emblematic, unquestionably, of the doctrine of his being the Vicegerent of Christ,--and on the bottom of a glass vessel of late date, found in the catacombs, the miracle of the striking of the rock is depicted, but at the side of the figure is the name, not of Moses, but of Peter,--for the Church had by this time advanced far in its assumptions. The story of Jonah appears also in four different scenes upon the walls of the chapels and burial-chambers. In the first, the prophet appears as being cast into the sea; in the second, swallowed by the great fish; in the third, thrown out upon dry land; and in the fourth, lying under the gourd. They are not found together, or in series; but sometimes one and sometimes another of these scenes was painted, according to the fancy or the thought of the artist. The swallowing of Jonah, and his deliverance from the belly of the whale, has already been referred to as one of the naturally suggested types of the Resurrection. When the prophet is shown as lying under a gourd, (which is painted as a vine climbing over a trellis-work, to represent the booth that Jonah made for himself,) the picture may perhaps have been read as a double lesson. As God "made the gourd to come up over Jonah, that it might be a shadow over his head, to deliver him from his grief," so he would deliver from their grief those who now trusted in him; but as he also made the gourd to wither, so that "the sun beat upon the head of Jonah that he fainted and wished in himself to die," it was for them to remember their utter dependence on the will of God, to prepare themselves for the sorrows as for the joys of life. Nor was this all; the story of Jonah was one especially fitted to remind the recent convert of the long-suffering and grace of God, and to suggest to those who were enduring the extremities of persecution the rebuke with which the