I encountered this mystifying aside (bolded) in the text of Anna Karenina. I assumed it might be a biblical reference, but upon checking, it doesn't seem that the biblical Rebecca was a slave. A quick search doesn't show any other potential references in English literature. I'm not well-read in Russian literature, so I don't know if it is a reference to a Russian-language text. Does anyone know what Tolstoy means?
It's a Constance Garnett translation, if that helps.
The below quote is from Chapter 34:
As for the baroness, [Petritsky] was sick to death of her, especially since she'd taken to offering continually to lend him money. But he had found a girl--he'd show her to Vronsky--a marvel, exquisite, in the strict Oriental style, "genre of the slave Rebecca, don't you know." He'd had a row, too, with Berkoshov, and was going to send seconds to him, but of course it would come to nothing. Altogether everything was supremely amusing and jolly. And, not letting his comrade enter into further details of his position, Petritsky proceeded to tell him all the interesting news.