Jon Stewart Jon Stewart

Jon Stewart will return to Fox News Channel's The O'Reilly Factor.

Though Stewart, who's scheduled to appear Wednesday, is a frequent critic of Bill O'Reilly's employer and it's fair to say the two hosts have differing political opinions, Stewart has a book to promote. Earth (The Book): A Visitors' Guide to the Human Race hits stores the day before Stewart's O'Reilly Factor appearance.

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When Stewart last appeared on O'Reilly's program, in February, the pair sparred over how Fox News covers the Obama administration.

Stewart will return the favor when O'Reilly appears on The Daily Show on Monday, Sept. 27.