This paper focuses on the numismatic evidence for an analysis of the formal icono- graphic and epigraphic imperial message. The official and precisely datable nature of coin- age renders it particularly reliable and significant. Although it cannot be determined with certainty in which cases the ruler himself was responsible for the symbols and legends cho- sen, and when the decision fell on officials like the comes sacrarum largitionum and the procuratores monetae. The introduction of Christian imagery, symbols and inscriptions was a slow and gradual process with three distinguishable phases. During the fourth century, from Constantine’s vision in 312 to the death of Theodosius I, the respect for former tradi- tions prevailed and Christian symbols played an intermittent and limited role. The grow- ing assertion of the labarum in the late fourth century gave way to that of the Victorious Cross under the Theodosian dynasty. The evolution was sealed at the end of this second phase, in the sixth and early seventh century, when Tiberius II and Heraclius chose the Cross as the unique motif of the reverse of the solidus and the silver hexagram respective- ly, the latter invoking Divine help in favour of the Romans. The third and last phase laid the foundation of the Mid- and Late Byzantine typology with the introduction of Christ image by Justinian II. He presented himself Servus Christi while the iconoclast emperor Leo III signed his new silver coins as ek theou (“by God”) and revived the Constantinian motto (“Jesus Christ conquers”) around a prominent Cross-calvary taken from the tradi- tional reverse type of the solidus.