Of the many tasks performed by the pontifical college perhaps none was of such lasting and widespread importance as the dedication of temple. Scholarship has cast much light on this topic by investigating the college's pronouncements on the legal validity of dedication (Tatum; Cohee) and elucidating the ceremony by which temple was formally dedicated (Nisbet; see also Bodel), but one element of pontifical involvement in dedication remains insufficiently explained. In this paper I investigate the pontiffs' decision to block Marcellus' dedication of temple to Honor and Virtue in order to show that their religious concerns regarding dedication embraced not only the correct performance of the ceremony of dedicatio, but also the temple's appearance and layout.Livy (27.25.6-10), Valerius Maximus (1.1.8), and Plutarch (Marc. 28.1-4) tell us that in 208 BCE M. Claudius Marcellus' attempt to dedicate temple to Honor and Virtue was blocked by the pontifical college. At issue was the temple's design. According to Livy and Valerius Maximus, Marcellus planned to house both deities in one cella. pontiffs, however, claimed that one cella could not rightly be dedicated to two deities, for if the temple were struck by lightning or if prodigy occurred within it, they could not know whether to make propitiatory sacrifice to Honor or to Virtue. Marcellus' solution (which appears to have met the pontiffs' objection) was to build for each deity its own temple.At first glance, this seems an odd solution. After all, the pontiffs had claimed it was wrong for one cella, not for one temple, to house two deities. Why did not Marcellus instead build two cellae in the temple, place statue of Honor in one and of Virtue in the other, and dedicate the whole structure to the pair? Why build separate temple for Virtue? answer may reside in comment of Servius, who claims (ad G. 3.16) that a place is always made sacred to the deity whose image is placed in the (nam ei semper sacratus numini locus est, cuius simulacrum in medio collocatur). arrangement of many Roman temples seems to corroborate this claim. Capitoline Temple, for example, though home to three deities (Juno, Jupiter, and Minerva) was yet technically known as the temple of Jupiter Optimus Maximus, apparently because Jupiter's cult statue occupied the middle cella, as we in fact know it did. Servius' statement may thus allow us to understand why Marcellus did not build another cella in the temple and dedicate the entire structure to Honor and Virtue. Such temple would house only two gods, neither of whom could occupy the middle position - there would in fact be no middle position. And with no god in the middle, the identity of the deity to whom the temple was sacratus would be unknown, and hence the procuration of any prodigy in the temple or of any lightning bolt that hit it would be impossible, for the pontiffs could not know which deity was thereby expressing anger and in need of placation. Because prodigies proclaimed or portended rupture in the pax deorum, such confusion about their procuration could be disastrous. Thus, in safeguarding Rome's favorable relationship with her gods, the pontiffs appear to have wielded considerable measure of authority over both the structures as well as the ceremonies fundamental to Roman religion. BIBLIOGRAPHYBodel. J. 'Sacred Dedications': A Problem of Definitions, in J. Bodel and M. Kajava (eds.) Dediche Sacre nel Mondo Greco-Romano: Diffusione, Funzioni, Tipologie (Rome 2009) 17-41.Cohee, Lloyd L., Jr. Decrees and Responses of the Roman Priesthoods during the Republic. Ph.D. diss, University of Colorado, Bolder, 1994.Nisbet, R. G. M. Tulli Ciceronis De Domo Sua ad Pontifices Oratio (Oxford 1939): 206-209.Tatum, W. J. The Lex Papiria De Dedicationibus, CP 88 (1993) 319-28.