Irenaeus Against Heresies Book V And again he says, in the Epistle to the Romans, "For if ye live after the flesh, ye shall die."[77] Origen Against Celsus Book V and we use every effort to "mortify the deeds of the flesh."[170] Origen Against Celsus Book VII It is certain also that a Christian will not make use of "the language of the flesh," having learnt as he has "to mortify the deeds of the body"[86] Celsus may indeed say of us that we "live with the body which is a dead thing; "but we have learnt, "If ye live after the flesh, ye shall die; but if ye by the Spirit do mortify the deeds of the body, ye shall live; "[138]