Biblical Greek (koi·neʹ) is the language in which the Christian Greek Scriptures were originally written (aside from Matthew’s Gospel, which was written first in Hebrew) and in which also appeared the first complete translation of the Hebrew Scriptures, namely the Greek Septuagint. As to structure, Greek is an inflectional language, achieving variety in expression by means of stems, prefixes, and endings.
Koi·neʹ developed from the classical Attic Greek. While Attic Greek contained many vernacular expressions, the Koi·neʹ added many more, making it more cosmopolitan and simplifying the grammar. While avoiding the artificial and pedantic style of some of the classical writers, the penmen of the Christian Greek Scriptures nevertheless used many classical words, elevating the koi·neʹ Greek, in dignity and restraint, far above the common everyday Koi·neʹ in the nonliterary Greek papyri, found mostly in Egypt.
Further, the Greek vocabulary is quite abundant and exact, enabling the Greek writer to make fine differentiation and to convey just the shade of meaning that he desires. For example, Greek makes a distinction between ordinary knowledge, gnoʹsis (1 Timothy 6:20), and intensified knowledge, e·piʹgno·sis (1 Timothy 2:4), also between alʹlos (John 14:16), meaning “another” of the same kind, and heʹte·ros, meaning “another” of a different kind. (Galatians 1:6) Therefore, the koi·neʹ Greek gained a richer, fuller, and more spiritual meaning in the context of the inspired Scriptures.