Roman Witness to Jewish Monotheism
The Egyptians worship many animals and monstrous images; the Jews conceive of one god only, and that with the mind alone: they regard as impious those who make from perishable materials representations of gods in man's image; that supreme and eternal being is to them incapable of representation and without end. Therefore they set up no statues in their cities, still less in their temples; this flattery is not paid their kings, nor this honour given to the Caesars.
Histories
Histories, Book V.5
p. 183
Tacitus, C. (1962). Tacitus: The Histories, with an English Translation by Clifford F. Moore; the Annals, with an English Translation by John Jackson. William Heinemann Ltd. http://books.google.co.uk/books?id=GpgdAAAAIAAJ&hl=&source=gbs_api