To dedicate is to consecrate with intention. Gettysburg was not merely a ceremony of oratory but of binding word to soil. Lincoln understood that the ground itself would carry the weight long after the speakers went home.
This is not unlike how we dedicate code, architecture, or love. We set something down and ask it to endure beyond us— constitutions, cathedrals, functions in modules—all are acts of faith that some pattern will be read faithfully after our fingerprints have been worn smooth by others' hands touching the same surface.