"Mugabe must be viewed as the 21st Century Hitler, a person seemingly without conscience or remorse, and a murderer," he said in a statement.
He called for churches to pray for Mugabe’s forced removal on 16 December.
Mugabe’s presidency had caused too much suffering of innocent Zimbabweans, and had led to untold casualties and deaths.
Seoka said the leadership of the Southern African Development Community and its structures had protected their "comrade in dictatorship" while international leaders had overwhelmingly called for Mugabe’s removal.
SADC members such as Botswana had, however, raised their voices in protest at the violation of human rights in Zimbabwe, expressing deep concern for the ongoing abuses which continued unchecked, he said.
"I believe it is now an opportune moment for all the church leaders to follow the retired Anglican Archbishop Desmond Tutu and the Archbishop of York, Dr John Sentamu, to call on God to cause the removal Mugabe from the office of the President of Zimbabwe."
He, however, said that calling on Mugabe to go was not going to help.
"He must be forcefully removed by all means necessary to stop further suffering of God’s children and save lives in that country.
"The church in South Africa has done this before with the apartheid regime and there is no doubt that God will hear our prayers even today."
Seoka said Mugabe should be arrested and tried, like his "comrade", former Liberian president Charles Taylor, by the International Court in the Hague for the atrocities he had committed during his tenure.
He challenged church leaders to call on their members to focus their prayers on the Day of Reconciliation, 16 December, for Mugabe’s removal, so that people may have a peaceful Christmas.
He further appealed to South Africans "agitating" that Zimbabwean refugees return to their country, to be patient with them until Mugabe was removed from office.
"We need to commit ourselves to assist the refugees from Zimbabwe in our midst, remembering that the one we call our Lord and Saviour was a refugee in Egypt, fleeing the Mugabe of that period, King Herod."
Seoka said compassion needed to be shown for those suffering in Zimbabwe as a result of human greed and power.