Yes, to become expert in it requires a lot of study. But actually, the very basic footing of it is quite easily to pick up, as it was for the many cultures Alexander brought under Hellenistic control. At one time it was taught to most British youths in the "public" schools, and to our children. It is especially simple to acquire if one has already learned about grammar in any well-structured language, and more so if one has learned the Greek alphabet.
http://www.bibletruths.net/Greek%20Course.htm
is an online course in Biblical Greek, consisting of about eight simple lessons which will greatly improve the serious disciple's spiritual maturity.
I recommend it, especially for the attitude and helpfulness of its instructor.
“It is especially simple to acquire if one has already learned about grammar in any well-structured language, and more so if one has learned the Greek alphabet.”
I grew up speaking Greek, Demotic. I went to “Greek School” in elementary school and learned to read and write katherevusa. In the altar we boys learned Byzantine Greek. Ancient and koine Greek came in high school and college. It’s a lovely language. When I speak or read it, quite literally my world view, my “phronema” changes. For that reason alone a Christian should make every effort to learn Greek.