During the zombie segment, Kirk Van Houten is one of the zombies that attacks the Simpson home. However, he also appears later, and normal, when the Simpsons reach the safe zone.
Marge asks, "what kind of civilized people eat the body and blood of their savior?" Cut to Rev. Lovejoy, who becomes uncomfortable as the punchline of this jab, apparently as one who believes this. Reverend Lovejoy is a Protestant, not a Catholic, and thus would not believe that the bread and wine of Christian communion are anything more than reminders of the ultimate atoning sacrifice of Christ (See 1 Corinthians 11:23-26). Catholics and E. Orthodox traditions tend to be the proponents of transubstantiation, believing the bread and wine actually become Christ's flesh and blood. This is a 12th century idea not found in scripture, thus would not be believed by Rev. Lovejoy.
Lisa doesn't want Homer to bash Bart with the book stating it's the last book in the world, but we see two books on Bart's bookshelf when Homer is strangling him.