What was one reason why Lincoln pushed for passage of the Thirteenth Amendment?

One reason Abraham Lincoln pushed for the passage of the Thirteenth Amendment was to ensure the permanent abolition of slavery in the United States. After the Civil War, he recognized that even a military victory would not guarantee the end of slavery unless it was enshrined in the Constitution. Lincoln believed that formal legislation would not only reinforce the moral imperative of emancipation but also prevent any future attempts to reinstate the institution of slavery.