He was evidently a brilliant but stubborn man, often embroiled in political controversies. He spent much of his life alternating between distinguished government service, exile, and retirement—both voluntary and involuntary. Among the positions he held were personal secretary to King Sŏnjo, second prime minister, general of the army, ambassador to China, royal inspector, and Magistrate of Kang'won Province.

He became the first Korean poet to provide for posterity a considerable body of work: at least 107 sijo are known, many of them dealing with his central themes of love of king and love of country. His poems are characterized by spare, elegant expression; density of meaning; the startling phrase; and the crisp use of irony—elements which have become so much a part of sijo tradition. His pen name was Songgang (Pine River).