"until all the wealth piled by the bondman's two hundred and fifty years of unrequited toil shall be sunk, and until every drop of blood drawn with the lash shall be paid by another drawn with the sword..."
See in text (Text of Lincoln's Speech)
In this passage, Lincoln reiterates the idea that the Civil War represents a punishment and payment for the sin of slavery. Lincoln expresses this idea using the image of blood; the every drop of blood exacted from slaves by their masters must be matched by blood spilled on the battlefields of the war. This image is purely figurative, but it is elegant and concrete enough to convey Lincoln’s point forcefully.