BENYOMEN SHVAYTSER (1833-1886)
He was born in Dvort (Warta), Poland, descended from a Hassidic family. He attended religious elementary school and yeshiva, became a follower of the Jewish Enlightenment, went through a variety of transformations, and eventually converted to Christianity in 1885. In Yiddish he published a satirical story: Yekele kundas (Yekele the joker) (1878), under the pen name Abash.
Source: Zalmen Reyzen, Leksikon, vol. 4.