Sentence:  ... I admit it to be not so much the duty as the privilege of an American citizen, to <WSD>acquit</WSD> this obligation to the memory of his fathers with discretion and generosity. ... [I]t is not the less true, that there are many ties, which ought to bind our feelings to the land of our fathers. It is characterstic of a magnanimous people to do justice to the merits of every other nation; especially of a nation with whom we have been at variance and are now in amity; and most especially of a nation of common blood. 
Meaning of the word marked with <WSD> tags:  To discharge (for example, a claim or debt); to clear off, to pay off; to fulfil.