Bishop Emeritus of Torit, Paride Tabat, is in the UK for talks with former Archbishop of Canterbury Rowan Williams on ways to bring the violence to an end.
The African nation has been beset with fighting since independence from its northern neighbours Sudan in 2011.
Since an attempted coup in December 2013 it's thought more than 1,000,000 people have been displaced inside South Sudan, with more than 400,000 people fleeing to neighbouring countries.
Bishop Paride said the Church had been "the hope of the people" and that "even now the Church had not left them".
He added: "The Church has been always the voice for the voiceless and it has been a shepherd.
"The lasting peace can come, this needs a lot of struggle, the people we're dealing with are traumatised.
"They have gone through many wars and they have a lot of pain and anger in them.
"It is our duty now, all, including the international community, to help, heal these people from the trauma that they are suffering from."
Bishop Paride is a member of the South Sudan Council of Churches and the Committee for National Healing, Peace and Reconciliation.
In 2013, the United Nations awarded him the Sergio Vieira de Mello Prize in recognition for his efforts in promoting peace in communities, in particular in establishing the Kuron Peace Village - a model community where people from different tribes live in harmony.
He also played a critical role as Chief Mediator of the Jonglei Peace Process, and continues to be extremely active across South Sudan.
The Bishop's talks are being organised by Christian Aid.
