Sartre's liberty, or the dream of Adam (Theology, philosophy, choice megarics)

The philosophy of Sartre is paradoxical: atheistic on principle, it is nevertheless built on a concept, the one of "liberty," which, in its philosophical working-out from Augustin, depends on an explicit or implicit theological context; moreover, Sartre expressly establishes a filiation between the liberty of Descartes' God and the one of the "Pour-soi," between the sin of Adam and the choice of "human reality." Must we consider these assertions as mere analogies or as something more decisive? Doesn't the revendication for man of an infinite liberty, like those of Christian God, lead to nonsense? More generally, the analysis of Sartre's thought becomes here a way to investigate the boundaries between philosophy and theology.