This was however but a small part of the training of Jerome. From his desert, as his spirit calmed, he carried on a great correspondence, and many of his letters became at once a portion of the literature of his time. One in particular, an eloquent and oratorical appeal to one of his friends, the Epistle to Heliodorus, with its elaborate description of the evils of the world and impassioned call to the peace of the desert, went through the religious circles of the time with that wonderful speed and facility of circulation which it is so difficult to understand, and was read in Marcella's palace on the Aventine and learnt by heart by some fervent listeners, so precious were its elaborate sentences held to be. This letter boldly proclaimed as the highest principle of life the extraordinary step which Melania, as well as so many other self-devoted persons, had taken--and called every Christian to the desert, whatever duties or enjoyments might stand in the way. Perhaps such exhortations are less dangerous than they seem to be, for the noble ladies who read and admired and learned by heart these moving appeals do not seem to have been otherwise affected by them. Like the song of the Ancient Mariner, they have to be addressed to the predestined, who alone have ears to hear. Heliodorus, upon whom all that eloquence was poured at first hand, turned a deaf ear, and lived and died in peace among his own people, among the lagoons where Venice as yet was not, notwithstanding all his friend could say. "What make you in your father's house, oh sluggish soldier?" cried that eager voice; "where are your ramparts and trenches, under what tent of skins have you passed the bitter winter? The trumpet of heaven sounds, and the great Leader comes upon the clouds to overcome the world. Let the little ones hang upon other necks; let your mother rend her hair and her garments; let your father stretch himself on the threshold to prevent you from passing: but arise, come thou! Are you not pledged to the sacrifice even of father and mother? If you believe in Christ, fight with me for His name and let the dead bury their dead." There were many who would dwell upon these entreaties as upon a noble song rousing the heart and charming the ear, but the balance of human nature is but rarely disturbed by any such appeal. Even in that early age we may in the greater number of cases permit it to move all hearers without any great fears for the issue.