Quote from : The Fall of Hyperion Book

... primitive times had required primitive obedience, that later generations evolved to the point where parents offered themselves as sacrifice - as in the dark knights of the ovens which pocked old earth history - and that current generations had to deny any command for sacrifice. Sol had written that whatever God now took in human consciousness - whether as a mere manifestation of the subconscious in all its revanchist needs or as a more conscious attempt at philosophical and ethical evolution - humankind could no longer agree to offer up sacrifice in God's name. Sacrifice and the agreement to sacrifice had written human history in blood.