Now the birth of Jesus Christ took place in this way. When his mother Mary had been betrothed to Joseph, before they came together she was found to be with child from the Holy Spirit. And her husband Joseph, being a just man and unwilling to put her to shame, resolved to divorce her quietly.
As in, Joseph was suspicious that Mary had laid with another man to conceive Jesus, i.e. produced a bastard.
The polemic Toldot Yeshu, which was written with the Christian, and not the Marcionite, Christ in view, has the following:
At the close of a certain Sabbath, Joseph Pandera, attractive and like a warrior in appearance, having gazed lustfully upon Miriam, knocked upon the door of her room and betrayed her by pretending that he was her betrothed husband, Yohanan. Even so, she was amazed at this improper conduct and submitted only against her will.
Thereafter, when Yohanan came to her, Miriam expressed astonishment at behavior so foreign to his character. It was thus that they both came to know the crime of Joseph Pandera and the terrible mistake on the part of Miriam. Whereupon Yohanan went to Rabban Shimeon ben Shetah and related to him the tragic seduction. Lacking witnesses required for the punishment of Joseph Pandera, and Miriam being with child, Yohanan left for Babylonia.
Miriam gave birth to a son and named him Yehoshua, after her brother. This name later deteriorated to Yeshu.
Thereafter, when Yohanan came to her, Miriam expressed astonishment at behavior so foreign to his character. It was thus that they both came to know the crime of Joseph Pandera and the terrible mistake on the part of Miriam. Whereupon Yohanan went to Rabban Shimeon ben Shetah and related to him the tragic seduction. Lacking witnesses required for the punishment of Joseph Pandera, and Miriam being with child, Yohanan left for Babylonia.
Miriam gave birth to a son and named him Yehoshua, after her brother. This name later deteriorated to Yeshu.
In both cases the Hebrew Jesus is believed to a bastard son.
If Bar-Abbas is referring to anything, the Hebrew Jesus, the rebel against the Roman forces.
Giuseppe's theories are proven, yet again, to be entirely baseless.