Speaking at a conference organised by religious equality group, Cutting Edge Consortium, the bishop compared opposing gay marriage to slavery, The Telegraph reports.
Holtam said: Before Wilberforce, Christians in this country saw slavery as having Biblical support for what was the God-given in the ordering of creation.
In South Africa, Apartheid was seen in the same way by the Dutch Reformed Church.
Within the churches, Christians conscientiously disagree about the interpretation and significance of the six Biblical passages referring to homosexuality. Holtam said a very big gap had opened up between the church and society because of the marriage debate.
Most people now see the Church s avoidance of equality legislation as immoral and it undermines us. The comments come as a group of leading Anglicans wrote an open letter in The Times on Saturday supporting gay marriage.