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:
From December 1539, Luther became implicated in the bigamy of Philip I, Landgrave of Hesse, who wanted to marry one of his wife's ladies-in-waiting. Philip solicited the approval of Luther, Melanchthon, and Bucer, citing as a precedent the polygamy of the patriarchs. The theologians were not prepared to make a general ruling, and they reluctantly advised the landgrave that if he was determined, he should marry secretly and keep quiet about the matter. As a result, on 4 March 1540, Philip married a second wife, Margarethe von der Saale, with Melanchthon and Bucer among the witnesses. However, Philip was unable to keep the marriage secret, and he threatened to make Luther's advice public. Luther told him to "tell a good, strong lie" and deny the marriage completely, which Philip did during the subsequent public controversy. In the view of Luther's biographer Martin Brecht, "giving confessional advice for Philip of Hesse was one of the worst mistakes Luther made, and, next to the landgrave himself, who was directly responsible for it, history chiefly holds Luther accountable". Brecht argues that Luther's mistake was not that he gave private pastoral advice, but that he miscalculated the political implications. The affair caused lasting damage to Luther's reputation.

Question:
What did this affair cause to Luther's reputation?

lasting damage