Introduction Chapter One: Trinitarian Soteriology: Towards a Theology of the One Sacrifice of Christ Chapter Two: Augustine and the One Sacrifice of Christ Interlude: The Mass Preceded by Mission Chapter Three: The Sacrifice of Christ in the Mass Interlude: The Mass Flows into Mission (and Back) Chapter Four: The Sacrifice of Christ in Mission Interlude: Both Mission and Mass Depend upon Ecumenism Chapter Five: The Sacrifice of Christ in Ecumenism Conclusion: Sacrificing the Church as the Church's Being