The Secret History by Procopius

How he unhesitatingly abolished laws when money was in question will now be shown in a few words. There was one Priscus in the City of Emesa, who was a skilful forger of others' handwriting, and a rare artist in such crime. It happened that the church of Emesa had a long time before inherited the property of a distinguished patrician named Mammian, of illustrious family and of great wealth. During Justinian's reign, Priscus inventoried all the families of the mentioned city, so as to find which were adequately rich to be worth plundering, and after he investigated their family history, and found ancient letters in their ancestors' handwriting, he forged documents purporting to be their agreements to pay to Mammian large sums of money which were supposed to have been left with them by him as a deposit.

The amount of money mentioned as an obligation in these forgeries was not less than one hundred gold centenaries. He also imitated very craftily the writing of a certain notary public whose office was in the Forum during Mammian's lifetime: a man of high reputation for truth and every other virtue, who used to draw up all the citizens' documents, fixing them with his own seal. To those who were in charge of ecclesiastical affairs at Emesa he gave these documents, after they agreed that he would get a share of the money to be obtained from the matter.