I learned Koine Greek in graduate school. There are a lot of resources published in the United States because Koine Greek is the language of the New Testament. One good book for beginners is A Primer of Biblical Greek by Clayton Croy. If you want to get a good sense of how the language works, there is a Youtube account called Daily Dose of Greek which translates verses of the Bible and provides grammatical and syntactical explanations.
I have lived in Greece for a couple of years and Modern Greek is very different but you can tell that Koine Greek is the basis of it. Maybe a good analogy is the difference between Middle English and Modern English.
Let me know if I can help you in any way!
Also how different is it from Greek that is spoke today?
The Greek in the New Testament is the so-called koine 'common language'. Based originally on the Greek of Athens, it was circulated throughout Alexander the Great's empire.
Thank you. Do you know of any good sources to learn from?
Modern Greek has many differences in grammar and even in vocabulary but learning it does help a lot in understanding Koine Greek, so you may consider learning it here on Lingq.
On the other hand, there is also Attic Greek. This one is very similar to Koine. Koine was initially based on the so-called "Great Attic" dialect, although it deviated from it to some extent over time. Still, it may pay to learn from a good book about Attic Greek, because there is simply a wider choice for it.
I like the Reading Greek series to get you started, because it is based on reading texts and it introduces you to the grammar and vocabulary gradually. To better memorize the vocabulary there are available Anki cards and a Memrise course: https://app.memrise.com/course/711947/jact-reading-greek-vocabulary/
After you have gone through it, get an online version of the Greek Bible and read a bit everyday. For a beginner the only difficulties in switching to the bible (Koine Greek) from Attic (the main form taught in Reading Greek) is getting used to the tt -> ss change (Attic glotta, tongue, becomes glossa; attic thalatta becomes thalassa and so on; this comes from the Ionic dialect which is also prsented in "Reading Greek) and to some changes verb forms, mostly because in Koine they are sometimes more regular than in Attic.
This is one of the sites that offer the New Testament in Greek with clickable words that show meaning and grammatical analysis: https://www.gntreader.com/#
I used to use a different site that also offered multilingual parallel texts and, besides the New Testament, also had the Septuaging Greek translation of the Old Testament, but I can't find it right now. You can always open another tab with an English version.
Hi Ftornay, your comments are always valuable and useful. So the gap between Modern Greek and Koine is smaller than the gap between Koine and Homeric Greek?
Hi, Jokojoko and thank you.
That' hard to say. Notice that both Homeric Greek and Koine Greek only exist nowadays as written languages. In pronunciation, for example, Koine is pretty close to modern Greek even if it still retained some more conservative features, such as ypsilon pronounced as "French u / Gernan ü". On the other hand a lot of grammar would still have been recognizable by someone from Homeric times. Some verbal moods that are absolutely absent from modern Greek still appeared occasionally in Koine, such as the optative and Koine used infinitives as a normal feature of the language, whereas they are absent from moder Greek.
To compound the problem, Greek speakers in Hellenistic and Roman times were very familiar with both Homeric and classic Attic. Classic Attic was considered by many a literary standard and a "proper" way to write and most texts live in a continuum from almost perfect Attic (for example, the works of Lucian of Samosata and the other "atticists") to a rather "vulgar" tongue close to the vernacular with everything in the middle.
So, which is further is very dubious and debatable. Languages evolve continuously. From the probable first version of the Illyad (maybe 4th century BC=?) to the writing of the New Testament there is a 500 year gap. From the second date to our times 2000 years have elapsed. So, I would say that Koine was closer to Homeric Greek than to modern Greek, but at the end of the day they are different dialects and stages of the same language. Just as Caesar's works and modern Spanish are stages of the same evolving tongue.