George Washington was generally skeptical of the role of political parties in a democracy. He believed that having different parties could potentially lead to sectionalism, which could threaten the unity of the nation. He also believed that the conflict that arises between different parties weakens the government, as they try to take the power for themselves and forget about the good of the nation as a whole.
The Legislative Branch is the most powerful branch of the United States government not only because of the powers given to them by the Constitution, but also the implied powers that Congress has.