Thank God It's Doomsday/References

Cultural references

 * The title is a reference to the popular saying,.
 * The movie Left Below is a parody of .
 * The song playing when Homer is throwing away his books on the Rapture is 's version of "Easy To Be Hard" from the musical .
 * God's chair is an manufactured by, except that God's chair floats and does not have a base.
 * In heaven, Leonardo da Vinci is shown drawing, with his left hand, a portrait of Dean Martin in the style of the.
 * Among the changing art pictures displayed above the bed in heaven are:
 * A painting of colored rectangles in the style of ;
 * The classic poster that sold 12 million copies;
 * The "" painting by (also used in Dutch Masters cigar boxes);
 * What appear to be like those painted by.
 * The song played as Homer enters heaven is "" from the opera  by.
 * The clock labelled Heaven is on or UTC+12 relative to the other clocks labelled London, New York and Tokyo.
 * God tells Homer that his son, Jesus Christ, went down to Earth and he doesn't know what happened to him, but his son hasn't been the same since. This is a reference to the.
 * When God turns back time, he exclaims "", a plot device meaning "God from the machine". It is used ironically since this was the act of the real God to solve an otherwise unsolvable problem, not the god from the mechanical contrivance that ancient Greek dramatists used for the same purpose.
 * In the scene at Moe's at the end of the episode, Homer and his pals are posed to resemble the fresco by Leonardo da Vinci, with Homer in the center as Jesus.
 * The skeleton of the crashed Duff blimp, with flames, is a reference to the.
 * Moe's sushi bar, "Tokyo Roe's", is a parody of, a voice broadcasting Japanese propaganda to Allied soldiers during World War II.
 * Krusty mentions he doesn't want to die next to Kathy Griffin.

Trivia

 * God is drawn with 5 fingers on each hand and 5 toes on each foot.
 * Homer knows the meaning of "eponymous."
 * The cart of wind chimes that Bart and Lisa back into at the mall carries the sign, "Tinkle in the Wind".
 * Celebrities in the Duff blimp include:
 * Bette Midler
 * Ron Howard
 * David Crosby
 * Joan Rivers
 * Rosie O'Donnell

Continuity

 * Charlie Brown is shown for the fourth time. The first time he was seen in his ghost costume in "Treehouse of Horror II", the second time a candle version of him was seen in "Grade School Confidential" and the third time as a costume in "Treehouse of Horror XIV".