Unveiled by The Film Stage, the clip sees Gandalf (Ian McKellen) give Bilbo (Martin Freeman) his first sword.
"I have never used a sword in my life," Bilbo protests, which prompts Gandalf to offer him some wise counsel on the true meaning of courage.
The sword, Sting, is the same sword Bilbo later passes on to Frodo (Elijah Wood) in The Lord of the Rings: The Fellowship of the Ring.
McKellen has admitted that he almost declined to appear in The Hobbit, and found certain aspects of the film challenging.
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The Hobbit: An Unexpected Journey will be released on December 13 in the UK, and December 14 in the US.
Watch the first TV spot below: