Letter - Vine's Expository Dictionary of New Testament Words
Letter[ 1,,G1121, amma ]
primarily denotes that which is traced or drawn, a picture;" then, "that which is written,"
(a) "a character, letter of the alphabet," 2 Corinthians 3:7; "written," lit., "(in) letters;" Galatians 6:11; here the reference is not to the length of the Epistle (Paul never uses gramma, either in the singular or the plural of his Epistles; of these he uses epistole, No. 2), but to the size of the characters written by his own hand (probably from this verse to the end, as the use of the past tense, "I have written," is, according to Greek idiom, the equivalent of our "I am writing"). Moreover, the word for "letters" is here in the dative case, grammasin, "with (how large) letters;"
(b) "a writing, a written document, a bond" (AV, "bill") Luke 16:6-Luke 16:7;
(c) "a letter, by way of correspondence," Acts 28:21;
(d) the Scriptures of the OT, 2 Timothy 3:15;
(e) "learning," John 7:15, "letters;" Acts 26:24, "(much) learning" (lit., "many letters"); in the papyri an illiterate person is often spoken of as one who does not know "letters," "which never means anything else than inability to write" (Moulton and Milligan);
(f) "the letter," the written commandments of the Word of God, in contrast to the inward operation of the Holy Spirit under the New Covenant, Romans 2:27, Romans 2:29; Romans 7:6; 2 Corinthians 3:6;
(g) "the books of Moses," John 5:47.
[ 2,,G1992, epistole ]
* See EPISTLE