In 458 BC, the Romans needed a dictator (an office reserved for extreme emergencies in Roman times) to respond to a massive enemy invasion. Cincinnatus was appointed, reached his command, defeated the enemy, and laid down his dictatorship after just 16 days. He returned to his farm and didn't bother with public service until called upon again years later.
He became a legend to Romans — twice given unbounded power and twice relinquishing it as soon as he had fulfilled his duty.
George Washington was called from his retirement at Mount Vernon to lead the Continental Army. When the war ended in 1783, Washington returned to his estate as a private citizen. While he would be called again four years later at the Constitutional Convention in 1787, he still followed the tradition of Cincinnatus and voluntarily gave up power after two terms.
Washington set an example for future presidents before term limits were enacted. Thomas Jefferson followed in his footsteps: first, he retired to his Monticello estate after serving as Secretary of State under Washington. Second, he retired to Monticello again after serving two terms as President.