This thesis is a work of Christian theology. Its purpose is twofold: firstly to develop an adequate understanding of reconciliation at the level of peoples and nations; and secondly to make a practical contribution to resolving the problems in Australia for the welfare of all the peoples, and of the land itself. The history of the relationships between the Indigenous and non-Indigenous peoples in Australia has left many problems, and no matter what the non-Indigenous people try to do, the Indigenous peoples of Australia continue to experience themselves as being in a state of siege. Trying to understand what is happening, and what can be done to resolve the problems for the peoples of Australia and the land, have been the implicit drivers for the theological development in this thesis. This thesis argues that the present generation in any trans-generational dispute is likely to continue to sin in ways that are shaped by the sins of the past, which explains why Indigenous peoples in Australia find themselves in a stage of siege, even when the non-Indigenous peoples are trying to pursue policies which they believe are for the welfare of all. The only way to resolve this is for the peoples of Australia to seek reconciliation. In particular, the non-Indigenous peoples need to repent, both of their own sins, and the sins of their forebears. Reconciliation processes have become part of the international political landscape. However, there are real concerns about the justice of pursuing reconciliation. An important part of the theological development of this thesis is therefore to show that pursuing reconciliation establishes justice. It is shown that the nature of justice, and of repentance, can only be established by pursuing reconciliation. Reconciliation is possible because God has made it possible, and is working in the world to bring reconciliation. Because land is an essential part of Indigenous identity in Australia, the history of land in court cases and legislation in Australia over the past half century forms an important case study in this work. It is shown that, although there was significant repentance within the non-Indigenous legal system in Australia, the degree of repentance available through that legal system is inherently limited, and so a more radical approach is needed in order to seek reconciliation in Australia. A final chapter considers what the non-Indigenous people of Australia need to do in order to repent.