Martin Luther 
An Open Letter on Translating [EPUB ebook] 

Martin Luther is called upon to defend his translations of the Bible, and he does so with his usual bombastic flair; however, he makes many excellent points concerning how translations work which are extremely helpful and insightful.
A fun little read, tackling several issues at once. Luther defends a dynamic equivalent translation method, he explains his use of the words sola fide—even though they are not in the original Latin or Greek texts, and he calls a bunch of people asses along the way. Well worth reading.