The Roman History · Amm. 23.3.2

There he stayed some days, preparing necessary supplies; and according to the custom of the district he offered sacrifices to the moon, which is religiously worshipped in that region; and it is said that while before the altar, no witness to the action being admitted, he secretly gave his own purple robe to Procopius, and bade him boldly assume the sovereignty if he should hear that he had died among the Parthians.

Ammianus Marcellinus · translated by C. D. Yonge · 1911 reprint
C. D. Yonge translation (preface dated February 1862); G. Bell and Sons, 1911; Project Gutenberg #28587
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