"And for the support of this Declaration, with a firm reliance on the protection of divine Providence, we mutually pledge to each other our Lives, our Fortunes, and our sacred Honor."

Why does Jefferson conclude with this statement?

Jefferson concludes the Deceleration of Independence with these lines to tie it in with religious importance and moral concerns.

Explanation:

The Declaration of Independence was a  document important enough that it needed recognition from all the citizen it was supposed to be valid on.

Thus, Jefferson invokes the providence in the last sentence so as to grant the venture into a new form of governance a divine ordain.  

The sentence also invokes the values of giving away lives, fortunes and honor to make it a statement of sacrifice completely devoid of personal gains for the signatories so as to make it more pious.

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