The essay authored by Thomas Paine, which was read to the Continental Army before the battle of Trenton in order to boost their morale is 'THE AMERICAN CRISIS'.
The book 'American Crisis' is actually a set of 16 pamphlets that was written in the eighteen century by Thomas Paine, who was an enlightenment philosopher of that time. The pamphlets were written during the period of American revolution and the author wrote the book purposely to encourage the American colonists to break away from their British oppressors. When war was finally declared, this book was read to the Continental Army in order to boost their morale and to give them a clear vision of what is at stake.