The last few lines of the Declaration of Independence state the following:
"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."
In these lines, we can see that the signers are promising to each other to sacrifice their lives, their fortunes and their honor in order to support this declaration. These lines show the commitment that the signers had towards independence, and the lengths they were willing to go to in order to achieve it.