Abstract
With the foundation of Sasanian dynasty, the first fully anthropomorphic representations of Ohrmazd appeared in ancient Iranian art. He was depicted in eight rock reliefs at Firuzabad, Naqsh-i Rajab (2 scenes), Naqsh-i Rustam, Tang-i Chugan (2 scenes) and Taq-i Bustan (2 scenes) while investing a beribboned diadem to the Sasanian king. The iconography of Ohrmazd was not a new one and before Sasanian period in Commagene and Bactria, the image of Ohrmazd had mainly created by imitating Greek-Roman prototypes. But the iconography of Ohrmazd in Sasanian rock reliefs was different. He was completely depicted in Iranian artistic fashion, and in some scenes, he carried bundles of barsam. Barsam is an implement carry by priests in ceremonial rituals. However, Avesta reveals that barsam was not only use by priests, but also hold by some deities including Ohrmazd. In Aban Yasht, Ahura Mazda (Middle Persian Ohrmazd) praises Aredvi Sura Anahita with the barsam. There are still questions about the figure of Ohrmazd and the sources of his iconography in Sasanian rock reliefs. So it is significant to review Zoroastrian texts again and study whether they affect the iconography of Ohrmazd or not. By analyzing and comparing the characteristics and details of iconographical elements of Sasanian rock reliefs and also regarding Zoroastrian written sources, the authors try to find the origin of these artistic models and the reason why Ohrmazd carries a bundle of Barsam at Firuzabad, Naqsh-i Rajab, Naqsh-i Rustam and Taq-i Bustan investiture scenes. The results show that the iconography of Ohrmazd was especially modeled after the royal art and the king himself. Furthermore, Some Zoroastrian texts reveal that Ohrmazd incarnate in Gētīg (material world) as an Ahlaw man or a priest and probably Sasanian artists consciously depicting him while carrying barsam in his hand(s).    
Keywords: Ohrmazd, Sasanian Rock Reliefs, Royal Appearance, Zoroastrian Priest, Zoroastrian Texts.

Introduction
By defeating the last Parthian king, Ardavan V, Artaxerxes I (224-240/1 CE) established an empire which was concentrated on centralization of Iranian state and unification of religion. To unify religion (Zoroastrianism), the iconoclastic movement was formed by Artaxerxes I. According to ancient sources, Artaxerxes I ordered to destroy idols, and instead many fires established throughout the empire; even some pre-Sasanian sacred fires were replaced by new ones. However, it seems such strictness does not prevent creating images of divine beings. There are evidences of iconography of Zoroastrian deities in Sasanian art. An important point is that in the Avesta and the Middle Persian texts, some deities were incarnated in human or animal forms and so the religious texts may be good sources for representations of deities. Interestingly archaeological evidence and written sources revealed different version of Zoroastrian in Armenia and Central Asian and idol-worship customs were prevalent there. In Commagene and Bactria, the image of Ohrmazd was mostly depicted according to Greek-Roman prototypes. On the contrary, the image of Ohrmazd as the superior Zoroastrian deity in Sasanian art was different and imitated from Iranian models. At Naqsh-i Rustam, the definite image of Ohrmazd contribute identification of him in other Sasanian rock reliefs. Due to the inscription, it was the only certain known evidence of Ohrmazd in Iranian art. At the same time, it is regarded as a significant document of the iconography of Zoroastrian divinities from the early Sasanian period. Despite extensive and diverse studies on Sasanian art and representations of Zoroastrian deities, including Ohrmazd, there are still ambiguities about the iconography of Ohrmazd and the sources of his visual images, the contribution of religious texts, and the influence of other iconographies of Ohrmazd on his representations in Sasanian art.

Discussion
Archaeological evidence and written sources shows that Ohrmazd occupied the highest status in ancient Iranian beliefs. The oldest and most definite references to him traced back on Achaemenian inscriptions (Lecoq, 1997: 176-276) and fortress tablets at Persepolis (Henkelman, 2008: 527-529). Furthermore, some scholars regarded the images of the winged disk with or without a bearded bust on Achaemenian monuments as the very ancient image of Ohrmazd (Lecoq, 1984; Skjærvø, 2014: 179-180). Contemporary with Parthian at about 30 BC, the Commagene king, Antiochus I erected statues of gods at Nemrud Daq (Herzfeld, 1941: 275). According to the inscriptions, one of the statues belongs to Oromasdes who was synchronized with Zeus (Widengren, 1986). Although he dressed in Persian fashion (Duchesne-Guillemin, 1978: 189) and holding barsam, but he was depicted like Zeus. On Kushanian coins, Ohrmazd was depicted again more likely after Greek models (Shenkar, 2014: 61-62), but under the name of Ōoromozdo or the abbreviated name Ōrom (Humbach, 1975: 139-140). For the first time during Sasanian period, Ohrmazd was represented in a fully anthropomorphic figure while investing a diadem to the Sasanian kings. At Naqsh-i Rustam, Ohrmazd synchronized with Zeus (Lukonin, 2005: 307), but he was depicted completely different and he appeared resemble to Sasanian kings probably for legitimization goals. Furthermore, Ohrmazd holding barsam in several reliefs. According to Bundahišn, Shāyist Nāshāyist, Ohrmazd incarnated as an Ahlaw man or a priest (Zot or Atravan) in Gētīg. He also praised Aredvi-sura-Anahita with barsam (Yš. 5. 17). So it seems that Sasanian artists deliberately depicted barsam in the hand of Ohrmazd to show him in the figure of Zoroastrian priest. As the image of Ohrmazd was not remained similar during Sasanian period, barsam appeared on Artaxerxes I’s rock reliefs and reemerge on Khosrow Parviz’s investiture at Taq-i Bustan.

Conclusion
Before Sasanian period, no definite representation of Ohrmazd is detected in Iran. The only images of the winged disk on Achaemenian and post-Achaemenian monuments in Pars attributed to Ohrmazd by some scholars. Contrary to Parthians, the iconography of deities in Sasanian period is much fewer. Although ancient sources attribute iconoclast movement to Artaxerxes I, but archaeological evidence manifest production of divine images. However it is important to distinguish cultic statues and portrayal of deities in the art. During Sasanian period fire-temples were established all over the kingdom and the cult of fire become the state religion. Erecting cultic statues was prohibited, however the images of deities including Ohrmazd produced in Sasanian art. Investiture ceremonies on rock reliefs show Ohrmazd in the shape of a royal figure while in some cases carrying a barsam like Zoroastrian priests. As Sasanian kings emphasize their legitimate claim during their sovereign, Ohrmazd depicted similar to the king. The representation of Ohrmazd in these monuments was completely in Persian mode and was against the image of him in Commagene or Kushan where he was depicted after Zeus. In the Middle Persian texts, Ohrmazd is invisible even amongst the sacred beings, except for the prophet Zardosht. He can be comprehend through wisdom and the power of comparison. However in the Pahlavi Rivāyat and Shāyist Nāshāyist, Ohrmazd described with a human appearance. In a passage from Shāyist Nāshāyist, Ohrmazd is an intangible spirits who appears in Gētīg in the body of the Mard-i Ahlaw (Just man). According to Bundahišn, Ohrmazd appears in the form of Zoroastrian priest in Gētīg. Also, he comes to the world as Zot. He is Atravan. So it is not strange that Ohrmazd depicted as a priest in some reliefs, while carrying a barsam.