Answer:
Alexander Hamilton believed that the best way for the new US to proceed was to have the federal government subsume the war debt of the States as a way to build credit.
Jefferson opposed this as he didn't like a strong federal government. He wanted more state independence and less fedral hold.
They agreed to move the Capital to the new Federal District between VA and MD and in return, the war debt could be subsumed by the federals.
This was a bad deal for Jefferson, but he went with it anyways.