Schneersohn was active in the Jewish religious resistance in the USSR, distributing funds and prayer books with the help of the Political Red Cross.

[6][7] The organization "provided material relief to needy Jewish refugees...founded Hebrew schools and synagogues, set up kosher soup kitchens and distributed clothing and money.

As Chana Arnon-Benninga describes, "From then on, until the liberation of Grenoble, on 22 August 1944, the children, the rabbi, his wife and the young adults, were hidden at different places in the Voiron area, some not seeing the light of day for weeks on end.

In his book on Jewish Résistance in France, Lucien Lazare[27] describes the role of Schneersohn:Having moved to Vichy, then to Marseille, the AIP had gathered together a community of sixty or so persons, composed of a Synagogue, a welfare office, a Yeshiva, a home for children and a workshop for vocational placement.

Rejecting at once emancipation, Zionism and Socialism, Chneerson only conceived Jewish existence in the jealous observance of rites and put up an impenetrable barrier against the influence of the environment and modernity.

His experience of secular persecutions had taught him to respond by establishing a community with unfailing cohesion, devoting itself to the study of sacred texts and the observance of the Mitzvot in the enthusiastic atmosphere of the hassidic tradition.

Chneerson had not discerned the novel and fatal character of the nazi threat, and the AIP was particularly vulnerable to the deportations.In "L'Auberge des musiciens",[29] Léon Poliakov describes Schneersohn ("red beard, limping slightly in his caftan according to the Polish custom") and his activities at Marseille:About a hundred or so persons prayed in the oratory of the rue Sylvabelle in a rich-looking building in of the most beautiful neighborhoods at Marseille [...] [There] two large rooms and a hall in the first floor, a kitchen and two rooms in the mezzanine [...].

The kitchen doesn't stay empty either: furtive shadows appeared in the evening and vanished in the morning; these are escapees of the internment camps of Vichy to whom the rabbi gives refuge.

One of the rooms of the first floor serves as an office and as a function room – a never-ending stream of Jewish miseries -, the other, the office of the rabbi, is at the same time a synagogue and a classroom; there weddings are celebrated and divorces are settled and even financial disputes.In his private diary, Raymond-Raoul Lambert, who headed the UGIF-Sud, the Vichy government's Union of French Jews, writes on 17 August 1943:The 28 (28 July 1943) I go, with Simone and the children, to visit a home for children close to Voiron, headed by an orthodox rabbin who resembles Rasputin.

The "assimilated" response by RRL [Raymond-Raoul Lambert] is not surprising, considering the content of the letter by the latter (2 August 1943, YIVO: RG 340, dossier 3) which deals into the details of his fantastic project to establish a Jewish State based on strictly orthodox principles.In a recent book entitled Les enfants de la Martellière, Delphine Deroo reconstitues the life of this institution.

And this moral resistance, that on my part I encounter in the insistence of rabbi Chneerson [Schneour Zalman Schneersohn] to strictly observe the religious laws – showing for him the very essence of his directly threatened Judaism -, strikes me and dazzles me by its strength and by its heroism.After the war, Schneersohn worked to promote non-consistorial Orthodox Judaism from his office at 10 rue Dieu, in the 10th arrondissement of Paris near Place de la République.

He continued to direct the AIP, organizing religious services and Jewish schools, as well as locating and rehabilitating children hidden in Christian homes during the war.