The Second Continental Congress convened in May 1775.
Harrison resided in north Philadelphia during the Congress with two roommates—his brother-in-law Peyton Randolph and George Washington.
The two men left him on his own when Randolph suddenly died, and Washington assumed command of the Continental Army.
Harrison was kept busy with the issues of funding and supplying Washington's army, and corresponded with Washington at length.

In the spring of 1775 an effort was made in the Congress to seek reconciliation with the King of Britain, through the Olive Branch Petition, authored by John Dickinson.
A heated debate resulted when Dickinson remarked that he disapproved of only one word he thought offensive in the petition, and that was the word "Congress."
Harrison angrily rose from his seat and replied, "There is but one word in the paper, Mr. President, of which I do approve, and that is the word 'Congress.'"
The petition passed and was submitted to the Crown, but remained unread by the King as he formally declared the colonists to be traitors.

In November of 1775, Harrison was appointed to a select committee to review the needs of the army.
He went to Cambridge, Massachusetts with Washington, Benjamin Franklin, and Thomas Lynch to assess the needs, as well as the morale, of the forces.
After a 10-day inspection, the committee concluded that the pay for the troops should be improved and the ranks should be increased to over 20,000 men.
Harrison then returned to Philadelphia to work closely with fellow delegates for the defense of his state as well as South Carolina, Georgia, and New York.

 
Harrison was in attendance until the session's end in July 1776, serving frequently as Chairman of the Committee of the Whole.
As such, he presided over the final debates of the Lee Resolution offered by Virginia delegate Richard Henry Lee.
This was the Congress' first expression of its objective of freedom from the Crown.
Harrison oversaw as well the final debates and amendments of the Declaration of Independence.
The Committee of Five presented Thomas Jefferson's draft of the Declaration on June 28, 1776, and the Congress resolved on July 1 that the Committee of the Whole should debate its content.
The Committee amended it on July 2 and 3, then adopted it in final form on Thursday, July 4.
Harrison duly reported this to the Congress, and gave a final reading of the Declaration.
The Congress unanimously resolved to have the Declaration engrossed and signed by those then present.

Harrison was known for an audacious sense of humor.
Even detractor John Adams conceded in his diary that "Harrison's contributions and many pleasantries steadied rough sessions."
Pennsylvania Delegate Benjamin Rush in particular recalled the Congress' atmosphere during a signing of the Declaration on August 2, 1776.
He described a scene of "pensive and awful silence," and said that Harrison singularly interrupted "the silence and gloom of the morning," as delegates filed forward to inscribe what they thought was their ensuing death warrant.
Rush said that the rotund Harrison leaned over the diminutive Elbridge Gerry, who was about to sign the Declaration, and said, "I shall have a great advantage over you, Mr. Gerry, when we are all hung for what we are now doing.
From the size and weight of my body I shall die in a few minutes and be with the Angels, but from the lightness of your body you will dance in the air an hour or two before you are dead."
The Second Continental Congress convened in May 1775. Harrison resided in north Philadelphia during the Congress with two roommates—his brother-in-law Peyton Randolph and George Washington. The two men left him on his own when Randolph suddenly died, and Washington assumed command of the Continental Army. Harrison was kept busy with the issues of funding and supplying Washington's army, and corresponded with Washington at length. 
In the spring of 1775 an effort was made in the Congress to seek reconciliation with the King of Britain, through the Olive Branch Petition, authored by John Dickinson. A heated debate resulted when Dickinson remarked that he disapproved of only one word he thought offensive in the petition, and that was the word "Congress." Harrison angrily rose from his seat and replied, "There is but one word in the paper, Mr. President, of which I do approve, and that is the word 'Congress.'" The petition passed and was submitted to the Crown, but remained unread by the King as he formally declared the colonists to be traitors.
In November of 1775, Harrison was appointed to a select committee to review the needs of the army. He went to Cambridge, Massachusetts with Washington, Benjamin Franklin, and Thomas Lynch to assess the needs, as well as the morale, of the forces. After a 10-day inspection, the committee concluded that the pay for the troops should be improved and the ranks should be increased to over 20,000 men. Harrison then returned to Philadelphia to work closely with fellow delegates for the defense of his state as well as South Carolina, Georgia, and New York.
 
Harrison was in attendance until the session's end in July 1776, serving frequently as Chairman of the Committee of the Whole. As such, he presided over the final debates of the Lee Resolution offered by Virginia delegate Richard Henry Lee. This was the Congress' first expression of its objective of freedom from the Crown. Harrison oversaw as well the final debates and amendments of the Declaration of Independence. The Committee of Five presented Thomas Jefferson's draft of the Declaration on June 28, 1776, and the Congress resolved on July 1 that the Committee of the Whole should debate its content. The Committee amended it on July 2 and 3, then adopted it in final form on Thursday, July 4. Harrison duly reported this to the Congress, and gave a final reading of the Declaration. The Congress unanimously resolved to have the Declaration engrossed and signed by those then present.
Harrison was known for an audacious sense of humor. Even detractor John Adams conceded in his diary that "Harrison's contributions and many pleasantries steadied rough sessions." Pennsylvania Delegate Benjamin Rush in particular recalled the Congress' atmosphere during a signing of the Declaration on August 2, 1776. He described a scene of "pensive and awful silence," and said that Harrison singularly interrupted "the silence and gloom of the morning," as delegates filed forward to inscribe what they thought was their ensuing death warrant. Rush said that the rotund Harrison leaned over the diminutive Elbridge Gerry, who was about to sign the Declaration, and said, "I shall have a great advantage over you, Mr. Gerry, when we are all hung for what we are now doing. From the size and weight of my body I shall die in a few minutes and be with the Angels, but from the lightness of your body you will dance in the air an hour or two before you are dead."
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