Reddit reviews New Testament Greek for Beginners

I used this book for an introductory course I took in high school (yes, I was fortunate enough to take Koine in high school) and I can attest to its wonderful accessibility and ease of use despite its great age. I also borrowed an Interlinear Bible from my youth pastor, which was extremely helpful. I loved taking Classical Greek - it was and still is one of my favorite courses of study, valuable as much for its deeply historical roots as for its potential to open Scripture to you on a whole new level. I certainly don't profess to any level of current literacy, but nevertheless I found even my short study highly interesting and rewarding in many lasting ways.

My professor in college (20 years ago) used Machen. It's a classic, and available for cheap.

My professor did try a modern book, but since the modern book didn't teach accents, he ultimately rejected it. And we switched to Machen.