Lincoln was quite skilled in his use of metaphors in "The Gettysburg Address." It was clear that he wanted to associate the process of birth, death, and rebirth with a political aim. These metaphors equated the life cycle with the moral aims of the Union Army in the Civil War. This can be seen in a couple of distinct areas. In the opening of the speech, Lincoln uses the metaphor of birth to communicate the origin of the nation: "...our nations brought forth on this continent, a new nation, conceived in liberty." The implication of such a metaphor is to convey how the nation's birth equates with liberty and freedom, connecting to the political cause of freedom. This cause was something that Lincoln understood as easily equatable to the North and what it sought to do in the Civil War. The implication of the birth metaphor is to suggest that the Northern cause is aligned with the origins of the nation.
The death metaphors that Lincoln employs help to underscore this sense of purpose. Lincoln makes the argument that those who died on the battlefield and in the war gave their lives for the cause that gave birth to the nation:
"We are met on a great battlefield of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that the nation might live."
In using the metaphor of death, Lincoln is able to pivot towards the Union cause as being sacred, linking the deaths of soldiers with being in line with the birth of the nation. Lincoln understood that this metaphor would help people see the conflict as more than a political issue, but an ethical issue which transcended political concerns. Even though Lincoln had to have been aware of the political context of the speech, it is his genius to pivot towards something larger and more cosmic in scope. The implication of using metaphors of death to "hallow" the ground upon which he stands is also to "hallow" the Union cause in the Civil War.
The rebirth metaphor is meant to galvanize people into action. Lincoln recognizes that the use of rebirth suggests that "these dead shall not have died in vain." In order for the cycle of life to continue, Lincoln suggests that Northerners must commit themselves to the cause of the Civil War in favor of the North. Those in support of the Union cause become part of something larger, envisioned in the birth of the nation and the death of the soldier in the Civil War. The implications are both spiritual and political. Spiritually, Lincoln wants citizens of the North to embrace the Union cause. Politically, Lincoln uses the rebirth metaphor to ensure that the Union will not waver in its fight with the South. It is Lincoln's rhetorical genius that the implications of the birth, death, and rebirth metaphors operate on both spiritual and political levels.