You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Martin_Luther

Context:
Luther was a prolific hymn-writer, authoring hymns such as "Ein feste Burg ist unser Gott" ("A Mighty Fortress Is Our God"), based on Psalm 46, and "Vom Himmel hoch, da komm ich her" ("From Heaven Above to Earth I Come"), based on Luke 2:11–12. Luther connected high art and folk music, also all classes, clergy and laity, men, women and children. His tool of choice for this connection was the singing of German hymns in connection with worship, school, home, and the public arena. He often accompanied the sung hymns with a lute, later recreated as the waldzither that became a national instrument of Germany in the 20th century.

Question:
What did Luther use as accompaniment to his hymns?

lute