The issue that divided pure Marxist socialists from revisionists was the interpretation and application of Karl Marx's theories. Pure Marxist socialists adhered strictly to Marx's original ideas and believed in the necessity of violent revolution to overthrow capitalist systems and establish a classless, communist society. They rejected any compromise with capitalist systems and advocated for a centralized and authoritarian approach to governance during the transition to communism. In contrast, revisionists, also known as social democrats, believed in adapting Marxist principles to the realities of their time. They advocated for gradual and democratic reforms within existing capitalist systems to improve the conditions of the working class. Revisionists sought to achieve socialist goals through political participation, social welfare programs, and collective bargaining rather than through violent revolution. This ideological divide led to significant disagreements within socialist movements in the late 19th and early 20th centuries.
I hope this helped!
~~~Harsha~~~