In the work of Nietzsche, sacrifice can only sacrifice itself over and over (in an eternal return of the same) because what it seeks to overcome (the nihilistic revelation of truth that sublates sacrifice's negation) makes this sacrifice of itself both necessary and useless. The truth is eternally postponed in a necessary sacrificed gesture that can only sacrifice itself, thereby rendering itself useless. In the attempt to step beyond nihilism, that is, in the attempt to negate (or sacrifice) nihilism, one repeats the negation characteristic of nihilism. one becomes inextricably implicated in the move of nihilistic sacrifice. The sacrifice of the sacrifice characteristic of nihilism, that is, the sacrifice of sacrifice, can only take place as (perform itself as) the impossibility (or eternally postponed possibility) of its realization. One, therefore, produces or performs an interminable step/not beyond, an incessant step beyond that eternally returns.
Research in Phenomenology
Keenan, Dennis K., "Nietzsche and the Eternal Return of Sacrifice" (2003). Philosophy Faculty Publications. 1.
Keenan, Dennis. "Nietzsche and the Eternal Return of Sacrifice." Research in Phenomenology 33 (2003): 167-185.