A former student of Jacques Derrida, his work is informed by patristic and mystical theology, phenomenology, and modern philosophy.

[1] Much of his academic work has dealt with Descartes and phenomenologists like Martin Heidegger and Edmund Husserl, but also religion.

God Without Being, for example, is concerned predominantly with an analysis of idolatry, a theme strongly linked in Marion's work with love and the gift, which is a concept also explored at length by Derrida.

He studied at the University of Nanterre (now the University Paris Ouest Nanterre La Défense) and the Sorbonne and then did graduate work in philosophy from the École normale supérieure in Paris from 1967 to 1971, where he was taught by Jacques Derrida, Louis Althusser and Gilles Deleuze.

[2] At the same time, Marion's deep interest in theology was privately cultivated under the personal influence of theologians such as Louis Bouyer, Jean Daniélou, Henri de Lubac, and Hans Urs von Balthasar.

[9] His awards include:[6][10] Marion's phenomenological work is set out in three volumes which together form a triptych[12] or trilogy.

This was addressed in Étant donné: Essai d'une phénoménologie de la donation (1997), a more conceptual work investigating phenomenological givenness, the saturated phenomenon and the gifted—a rethinking of the subject.

[14] Marion claims that he has attempted to "radically reduce the whole phenomenological project beginning with the primacy in it of givenness".

[16] This is based on the argument that any and all attempts to lead phenomena back to immanence in consciousness, that is, to exercise the phenomenological reduction, necessarily results in showing that givenness is the "sole horizon of phenomena"[17] Marion radicalizes this argument in the formulation, "As much reduction, as much givenness",[18] and offers this as a new first principle of phenomenology, building on and challenging prior formulae of Husserl and Heidegger.

", is criticized on the basis that the things in question would remain what they are even without appearing to a subject—again circumventing the reduction or even without becoming phenomena.

These phenomena may be conventionally impossible, and still occur because their givenness saturates the cognitive architecture innate to the observer.