The author argues that the philosophical position of Karl Marx was primarily shaped by three determinants. The first was the traditional Jewish culture, with its high esteem for intellectual effort, for the genius reflected in intellectual discoveries, and for the ambition that influenced interesting life plans and culminated in some visions of an ultimate end in life. The second was neo- -Hegelianism, which Marx himself recognized as a dominant factor in his thought. Thirdly, Marx was affected by Martin Luther, and this influence is in the focus of this paper. The author clams that both Luther and Marx believed that the essential trait of specifically human existence arises from hard work of any kind except the dullest. Both were bewildered by ideological gullibility and blindness of the masses. Both were convinced that this boundless credulity was sustained by fear of eternal damnation spread by the official church and by slave mentality. Finally both claimed that this noxious influence could only be overcome by a revolution in life conditions and by new social ideas. Each, however, entertained a different conception of that desirable revolution.