Jehovah's Witness
From Tardis Wiki, the free Doctor Who reference
Jehovah's Witnesses were a group of Christians that worshiped the God Jehovah.
The leader of the Jehovah's Witnesses suggested that the god of the Krikkitmen listen to a variation of the song known as Amazing Grace. (PROSE: Doctor Who and the Krikkitmen)
When Iris Wildthyme heard a knock at the door of Pink Gables, she thought that it must be a Jehovah's Witness. (AUDIO: Dark Side)