Simon ben Kosiba, surnamed Simon bar Kochba ("son of the star") was a Jewish Messiah. Between 132 and 135, he was the leader of the last resistance against the Romans. After the end of the disastrous rebellion, the rabbis called him "Bar Koziba", which means "son of the lie".
One of the most important texts on the subject can be found in the History of the Church by the Palestinian bishop Eusebius of Caesaraea (260-c.340). In this work, he sometimes quotes older sources, such as Ariston of Pella and Justin, who were both contemporaries of the revolt of Bar Kochba. Here is the quote from Justin.
Justin, First Apology
[31.5-6] For in the present war it is only the Christians whom Barchochebas, the leader of the rebellion of the Jews, commanded to be punished severely, if they did not deny Jesus as the Messiah and blaspheme him.