It was not the mere matter of the separation of the colonies from the motherland; but something in the Declaration giving liberty, not alone to the people of this country, but hope to the world for all future time. It was that which gave promise that in due time the weights should be lifted from the shoulders of all men, and that all should have an equal chance. This is the sentiment embodied in that Declaration of Independence.

Abraham Lincoln (1809-1865) American lawyer, politician, US President (1861-65)

Speech (1861-02-22), Independence Hall, Philadelphia, Pennsylvania
    (Source)

Text as reported in the Philadelphia Inquirer (1861-02-23).

The New York Tribune account gave for the second clause, "but that sentiment in the Declaration of Independence which gave liberty."