Thomas Jefferson opposed the creation of a national bank primarily because he believed that the Constitution did not grant Congress the authority to establish such an institution. Jefferson was a strict constructionist, meaning he interpreted the Constitution narrowly and believed that the federal government should only have powers explicitly outlined in the document.
He argued that the establishment of a national bank would overstep these constitutional limits and concentrate too much financial power in the hands of the federal government, which he feared could lead to tyranny. Jefferson also believed that a national bank would favor the interests of the wealthy, particularly in the Northern states, at the expense of agriculture and agrarian society, which he championed.
In summary, while concerns about economic stability, state power, and the safe deposit of government money were factors in the broader debate, Jefferson's primary argument against the national bank was rooted in his interpretation of the Constitution and his desire to limit federal power.