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 is honoured on 18 February with a commemoration in the Lutheran Calendar of Saints and in the Episcopal (United States) Calendar of Saints. In the Church of England's Calendar of Saints he is commemorated on 31 October.

Question:
When is Luther commemorated in the Lutheran Calendar of Saints ?

18 February