The cloak that I left at Troas - On the situation of Troas, see the notes on Acts 16:8. It was not on the most direct route from Ephesus to Rome, but was a route frequently taken. See also the introduction, section 2. In regard to what the “cloak” here mentioned was, there has been considerable difference of opinion. The Greek word used (φελόνης phelonēs, - variously written φαιλόνης phailonēs, φελόνης phelonēs, and φελώνης phelōnēs), occurs nowhere else in the New Testament. It is supposed to be used for a similar Greek word (φαινόλης phainolēs) to denote a cloak, or great-coat, with a hood, used chiefly on journeys, or in the army: Latin, “penula.” It is described by Eschenberg (Man. Class. Lit., p. 209) as a “cloak without sleeves, for cold or rainy weather.” See the uses of it in the quotations made by Wetstein, in loc.
Others, however, have supposed that the word means a traveling-case for books, etc. So Hesychius understands it. Bloomfield endeavors to unite the two opinions by suggesting that it may mean a “cloak-bag,” and that he had left his books and parchments in it. It is impossible to settle the precise meaning of the word here, and it is not material. The common opinion that it was a wrapper or traveling-cloak, is the most probable; and such a garment would not be undesirable for a prisoner. It should be remembered, also, that winter was approaching 2 Timothy 4:21, and such a cloak would be particularly needed. He had probably passed through Troas in summer, and, not needing the cloak, and not choosing to encumber himself with it, had left it at the house of a friend. On the meaning of the word, see Wetstein, Robinson, Lex., and Schleusner, Lexicon. Compare, also, Suic. Thes ii. 1422. The doubt in regard to what is here meant, is as old as Chrysostom. He says (Homily x. on this Epistle), that the word φελόνην phelonēn denotes a garment - τὸ ἱματίον to himation. But some understood by it a capsula, or bag - γλωσσόκομον glōssokomon,” (compare the notes on John 12:6), “in which books, etc. were carried.”
With Carpus - Carpus is not elsewhere mentioned. He was evidently a friend of the apostle, and it would seem probable that Paul had made his house his home when he was in Troas.
And the books - It is impossible to determine what books are meant here. They may have been portions of the Old Testament, or classic writings, or books written by other Christians, or by himself. It is worthy of remark that even Paul did not travel without books, and that he found them in some way necessary for the work of the ministry.
Especially the parchments - The word here used (μεμβράνας membranas, whence our word “membrane”), occurs only in this place in the New Testament, and means skin, membrane, or parchment. Dressed skins were among the earliest materials for writing, and were in common use before the art of making paper from rags was discovered. These “parchments” seem to have been something different from “books,” and probably refer to some of his own writings. They may have contained notes, memorandums, journals, or unfinished letters. It is, of course, impossible now to determine what they were. Benson supposes they were letters which he had received from the churches; Macknight, that they were the originals of the letters which he had written; Dr. Bull, that they were a kind of common-place book, in which he inserted hints and extracts of the most remarkable passages in the authors which he read. All this, however, is mere conjecture.