Sfar is considered one of the most important artists of the new wave of Franco-Belgian comics. Many of his comics were published by L'Association which was founded in 1990 by Jean-Christophe Menu and six other artists. He also worked together with many of the new movement's main artists, e.g. David B. and Lewis Trondheim. The Donjon series which he created with Trondheim has a cult following in many countries.

Some of his comics are inspired by his Jewish heritage as the son of Jewish parents (an Ashkenazi mother and a Sephardic father). He himself says that there is Ashkenazi humor in his Professeur Bell series (loosely based on Joseph Bell), whereas Le chat du rabbin is clearly inspired by his Sephardic side. Les olives noires is a series about a Jewish child in Israel at the time of Jesus. Like Le chat du rabbin, the series contains a lot of historical and theological information.

His main influences are Fred and André Franquin as well as Marc Chagall, Chaim Soutine, Will Eisner, Hugo Pratt and John Buscema.