“What did Adam say on the day before Christmas?”/“It’s Christmas, Eve.”

A popular Christmas riddle is:
 
Q: What did Adam say the day before Christmas?
A: “It’s Christmas, Eve.”

 
The riddle has been cited in print since at least 1977. The joke sometimes has “the night before Christmas” instead of “the day before Christmas.”
 
“What did Adam say on the day before New Year’s?”/“It’s New Year’s, Eve” is a similar riddle.
   
   
21 December 1977, Orlando (FL) Sentinel, Sentinel Star, pg. 11, col. 4:
What did Adam say the day before Christmas?
 
9 February 1981, St. Louis (MO) Post-Dispatch, “A Prize In Every Box” by Elaine Viets, sec. 1, pg. 8D, col. 5:
Here’s a sample riddle: “What did Adam say before Christmas? It’s Christmas, Eve.”
 
Google Books
May 1982, Boys’ Life, “Think & Grin,” pg. 73, col. 2:
Bert: What did Adam say before Christmas?
Bob: I don’t know.
Bert: It’s Christmas, Eve. — Michael Myers, Westminster, Md.
 
Google Books
The Zaniest Riddle Book in the World
By Joseph Rosenbloom
Illustrated by Sanford Hoffman
New York, NY: Sterling Publishing Company, Inc.
1984
Pg. 64:
What did Adam say on the day before Christmas?
“It’s Christmas, Eve.”
 
Twitter
robinannl
‏@robinannl
What did Adam say on the day before Christmas?
It’s Christmas, Eve! Bahahaha
9:18 AM - 2 Dec 2008
 
Twitter
spacefrog29
‏@Spacefrog29
What did Adam say the day before Christmas?
Answer: it’s Christmas Eve
8:48 AM - 10 Dec 2008
 
Google Books
Christmas Crackers
By Matt Wilce
Lulu Publishing (Lulu.com)
2012
Pg. ?:
What did Adam say on December 24th?
It’s Christmas, Eve.
   
Reddit—Jokes
What did Adam say to Eve on the day before Christmas?
submitted December 22, 2013 by Blackwind123
“It’s Christmas, Eve.”
 
Google Books
Teacher’s Joke and Story Book
Collected by Stanley B Graham
Bloomington, IN: AuthorHouse
2016
Pg. ?:
Q. What did Adam say to Eve on the day before Christmas?
A. It’s Christmas, Eve