In Timaeus Plato defines cosmos as “the sanctuary of eternal gods.” Except for the demiurge, he speaks of other gods he calls the children of god (paides, 43a), to which the demiurge leaves the birth of mortal beings (41b–41e). They are called young gods (42d). These gods have become, but imperishable. These are visible gods. Most of the interpreters of this mythical tale from Timaeus holds that it applies to astral deities. In addition to the gods that can be seen, Plato also mentions some other invisible deities. Some of them he calls demons. But what are Plato’s ‘lower’ deities really? This issue was dealt with by many interpreters of his philosophy. In this paper, we are primarily interested in Calcidius’s, and then Herman Dalmatin’s point about it. It is known that Herman, in his cosmology exposed in De essentiis, largely relied on Calcidius’s translation and commentary on Timaeus. But speaking of heaven as the second cause of creation, the middle one in the cosmic hierarchy, he develops one remarkable astrological interpretation of heaven and heavenly gods (spiritus). The influence of Arab writers and especially Ptolemy, which was mediated to Herman by Arab authors, is largely recognized in this part of his philosophy. In the paper we ask whether the emphasis on the meaning of astrology in Herman is indeed the result of exclusively Arab influences or the elements of astrological interpretation of Timaeus that we find in later Plato’s interpreters such as Calcidius could serve as an incentive for Herman’s emphasis on the role of astrology in interpreting the world. We are trying to answer that question primarily by analyzing Calcidius’s interpretation of the place from Timaeus 37d–43a, that is, the part where Platon mentions other gods in several places, and then Herman’s expositions of heaven and heavenly spirits, pointing at the same time ambiguities regarding the interpretation of Timaeus we find in Calcidius and those that are related to the understanding of the actions of heavenly spirits in Herman.