The bishop’s vote in Tynwald creates a “spiritual voice in to public life” the outgoing bishop has said.
Peter Eagles, who took his last service on Saturday, said it was difficult at times for elected MHKs to vote against strong public opinion on an issue.
But the bishop’s position meant the feelings of those in the minority could be “recorded in the democratic process” he said.
There have been two attempts to remove the vote during Peter Eagles’ tenure.
Bishop Eagles said it could be “quite hard for an elected politician to vote against” strong public opinion but the bishop “may do it for a variety of reasons”.
“If everyone else is going to say yes, that’s fine. But I think the bishop can say no sometimes.”
He said while spiritual and the political interests often ran “along parallel lines” they could diverge at times, which was why the vote was crucial.
Although potentially “controversial” to some, without the vote the bishop’s presence would “become simply a sort of chaplaincy rather than a spiritual voice in public life, which I believe is really important”, he said.
While Bishop Eagles’ successor will not be in place for “several months” he said the diocese is “secure”.
He said the retention of the title of the diocese of Sodor and Man was “indicative of a really unique history” and there was “no appetite for that to be lost”.
While the island belongs to the Church of England, its status as an independent, separate diocese “says to the wider world that the church on the Isle of Man is a distinct thing, it’s a Celtic construct”.
Reflecting on his time on the island, Bishop Eagles said he had developed a “very deep love” for the island and its people.