The identity of a culture is oftentimes reflected in the respective language. This makes learning a language integral for understanding the culture. Additionally, learning the language enables you to read the original sources and to create your own interpretation of them independent from the influences of original translators.
When your field of study is an ancient culture, you most certainly will have the problem that the ancient language isn't consistent with its modern equivalent or isn't even spoken any more at all. This makes learning, apart from an university course, so much more difficult, but luckily there are persons sharing their knowledge with others.
Recently I stumbled upon an interesting sub-reddit on reddit.com. In r/IntroAncientGreek, reddit user Nanocyborgasm is publishing lessons to learn ancient Greek. For example, the first lesson covers the alphabet, pronunciation, and intonation of the language. The idea for the sub-reddit was also born on reddit in r/languagelearning. Nanocyborgasm, who studied classics, but actually works as a medical doctor, writes the lessons out of pure admiration and fascination for ancient Greek, and answers questions from the other users. At the time of this post, there are an impressive 24 lessons available, divided in multiple sub-lessons. Of course, the sub-reddit is not a real language course as exercises to practice the theoretical knowledge are still missing. However, Nanocyborgasm is thinking about ways to solve this problem.
Considering today's trend of education becoming more and more of a luxury good, we can thank people like Nanocyborgasm, who freely share their knowledge with others.