Numerous Jews took part in the various movements of the French Resistance during WW2. However some chose to join the M.J.S. (Mouvement de Jeunesse Sioniste) to bring specific help to the Jews that needed it.
Paul Giniewski who was an active member of the M.J.S. during the war has just written a book about this organization and its activities.
Indeed unlike the majority of the French population, French Jews, as well as the foreign Jews who had fled Germany and other Nazi-occupied territories, needed forged papers, hiding places and money to stay alive.
The movement was set up in 1942 and its creators saw their mission as being Jewish rescuers of Jews. They established their headquarters in the maquis in a chalet near Grenoble and joined forces with other Jewish rescue groups to smuggle Jewish adults and children into Switzerland and Spain.
They also worked with other French Resistance organizations, considering the liberation of France as part of their duty as French citizens. In fact Paul Giniewski recalls that he forged papers for French partisans who were also policemen. What’s more the organization occasionally got help from loyal French priests. Thus when he and other Jewish partisans were arrested by the French militia, a local priest intervened before they were executed and they were freed.
The M.J.S. was made up of right and left-wing Jews, some were religious while others saw themselves as atheists. Rabbi René Kapel was their chaplain and offered spiritual help along with lectures about Jewish history and Judaism.
Unfortunately the book which recounts these events, Une Résistance juive. Grenoble : 1943-1945, has not been published yet but I am very eager to read it.