Samantha says her mother, Endora, gets so upset over Halloween each year that she flies to the South of France "til it all blows over." In a later episode, however, Samantha (and Darrin, by proxy) are invited to Endora's "annual" Halloween bash.
Bertha makes the comment that, if the mortals ever did find out they were witches, they'd better take out lots of fire insurance. Samantha comments, "Oh Bertha, they stopped burning us years ago." In a subsequent episode, Samantha and Darrin find themselves in old Salem, and Samantha makes a speech about how the people they've put on trial couldn't possibly be witches because no mere ropes or binds could hold one; she then causes her own binds to disappear.
When tea is served at the start of the program Bertha places her cookie on her tea cup plate. In the next shot the cookie has disappeared.
One of the witches in this episode is "Mary", a contradiction to Asher's direction that all witches names end in "A".