Leyer und Schwert (Lyre and Sword) (modern German spelling Leier und Schwert) is a patriotic opera in five acts composed by Wendelin Weißheimer to a libretto by Louise Otto-Peters. Also known as Theodor Körner, the opera was composed in 1863/64 and premiered in Munich in 1872. The libretto is based on an episode in the life of the German poet and soldier Theodor Körner.