In the course of time the Cross itself seems to have been looked on, not so much as a suggestion of the Crucifixion, but as a type or emblem of Christ. A striking and curious example of this is to be found on a tomb in the church of S. Apollinare at Ravenna, where the artist has depicted the Transfiguration in a strange union of realism and symbolism. Moses and Elias are on either side, and the hand above suggests the Father, but three sheep stand for the chosen apostles, and in the centre is, not Christ, but the Cross. It may, perhaps, have been the perception of such a tendency which led the Greek Fathers at the Council in Trullo, in 692, to feel that the time had come for a more emphatic assertion of the personality and human nature of the Redeemer in sacred art. Thus, at any rate, they decreed:--"We order that, instead of the Lamb, our Lord Jesus Christ shall be shown hereafter in His human form in the images; so that, without forgetting the height from which the Divine Word stooped to us, we shall be led to remember His mortal life, His passion, and His death, which paid the ransom for mankind." The alteration, however, was completed as cautiously as it had been begun, even the method of production partaking of the restraint exhibited in the development of the subject. The earliest crucifixes probably had the figure simply etched in outline, then it was painted upon the cross, and last of all it became a partial or complete relief. The last stage was not reached, unless in a few exceptional cases, until the ninth century. The earliest crucifix in the catacombs is of the seventh or eight century, and Pope John VII., in 706, dedicated the first mosaic example in St. Peter's at Rome. Benedict Biscop, Abbot of Jarrow (died 690), brought from Rome the first picture of the crucifixion of which we hear in the north of England. S. Augustine advancing with his monks to his first conference with King Ethelbert of Kent, was preceded by a silver cross and a crucifixion painted on a panel. Now and again an iconoclastic spirit revealed itself in opposition to the growing use, not only of the crucifix but of images of saints and patriarchs, but it made no headway in the west. Serenus, Bishop of Marseilles, having broken down some images in a church, was reproved by Pope Gregory, on the ground that "in paintings on walls those who are unable to read books can read what in books they cannot." In the east, however, the movement aroused much bitterness, and led even to persecution. Leo the Isaurian in 726, began an attack on all use of images, and a Council at Constantinople in 752, rejected them altogether. This decree was not accepted generally as final, but in the end the eastern church settled down under a compromise, which is still maintained, by which pictures in painting, mosaic, or engraving, are permitted, but all reliefs and statutes are forbidden.