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Hastings' Dictionary of the New Testament [1]

The Gr. term (τὸ ξύλον, lit.[Note: literally, literature.]‘the wood’) translation‘stocks’ in Authorized Versionand Revised Versionis used to denote a wooden framework containing holes, in which the feet of criminals were confined. This ancient mode of punishment (cf.  Job 13:27;  Job 33:11) survived in lands further west till a comparatively recent period. Among both Greeks and Romans it was employed in the case of freeborn malefactors as well as slaves. When Paul and Silas were thrown into the inner dungeon of the prison at Philippi, the jailer, who was charged by the Roman magistrates (known as the Duumviri) to keep the prisoners safely, for greater security took the precaution of enclosing their feet in the stocks ( Acts 16:24). This infliction was part of the shameful treatment endured at Philippi to which the Apostle afterwards referred in his First Epistle to the Thessalonians ( 1 Thessalonians 2:2).

W. S. Montgomery.

Fausset's Bible Dictionary [2]

(1) Μahpeketh ;  Jeremiah 20:2;  Jeremiah 29:23, from Hapak "rack"; our "pillory"; the word implies the body was bent, the arms and neck as well as the leg being confined. Prisons had usually a chamber for the purpose called "the house of the pillory" (  2 Chronicles 16:10 , Kjv "Prison House") . The other Hebrew term,

(2), Sad , is our "stocks" ( Job 13:27;  Job 33:11;  Acts 16:24), in which the feet alone are confined; the Roman nervous, which could be made at the jailer's will an instrument of torture by drawing asunder the feet;

(3)  Proverbs 7:22, rather "a fetter"; Akasim , used for "the tinkling ornaments on women's feet" in  Isaiah 3:16-18. The harlot's tinkling foot ornaments excite the youth's passions, all the while he knows not that her foot ornaments will prove his feet fetters; "to love one's fetters, though of gold, is the part of a fool" (Seneca). He sports with and is proud of his fetters as if they were an ornament, or put on him in play.

Smith's Bible Dictionary [3]

Stocks. (An Instrument Of Punishment, Consisting Of Two Beams, The Upper One Being Movable, With Two Small Openings Between Them, Large Enough For The Ankles Of The Prisoner. - Editor). The term "stocks" is applied, in the Authorized Version, to two different articles, one of which answers rather to our Pillory , inasmuch as, the body was placed in a bent position, by the confinement of the neck and arms, as well as the legs, while the other answers to our "Stocks", the feet alone being confined in it.

The prophet, Jeremiah, was confined in the first sort,  Jeremiah 20:2, which appears to have been a common mode of punishment in his day,  Jeremiah 29:26, as the prisons contained a chamber for the special purpose, termed "the house of the pillory."  2 Chronicles 16:10. (Authorized Version, "prison-house"). The stocks, properly so called, are noticed in  Job 13:27;  Job 33:11;  Acts 16:24. The term used in  Proverbs 7:22, (Authorized Version, "stocks"), more properly means a fetter.

Morrish Bible Dictionary [4]

Various words are used for these instruments of punishment.

1. mahpecheth, a wooden frame in which the feet, hands, and neck of a person were so fastened that his body was kept bent. Jeremiah was subjected to this punishment.  Jeremiah 20:2,3 .

2. sad: stocks in which the feet were shut up.  Job 13:27;  Job 33:11;  Acts 16:24 (ξύλον).

3. tsinoq: stocks which confined the hands and the feet.  Jeremiah 29:26 .

4. ekes, 'a fetter or ankle-band.'   Proverbs 7:22 .

Vine's Expository Dictionary of NT Words [5]

1: Ξύλον (Strong'S #3586 — Noun Neuter — xulon — xoo'-lon )

"wood," is used of "stocks" in  Acts 16:24 . See Staff , Tree , Wood.

Holman Bible Dictionary [6]

 Job 13:27 Jeremiah 29:26 Acts 16:24

Hastings' Dictionary of the Bible [7]

Stocks . See Crimes, 9  ; Prison, p. 756 b .

King James Dictionary [8]

STOCKS. See under Stock.

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [9]

(in the plur.) is the rendering in the A.V. of the following Heb. and Gr. words

1. The מִהְפֶּכתֵ , Mahpeketh ( Jeremiah 20:2;  Jeremiah 29:26;  2 Chronicles 16:10), is supposed by some to have been rather a sort of pillory in which the head and hands were fastened than an instrument for fastening by the feet; yet, as the word, is derived from הָפִךְ , To Twist, it may properly represent the Rack for wrenching apart the joints of the entire person (see Scheid, in the Diss. Lugd. p. 986; Bochart, Hieroz. 1 , 694). It may perhaps be compared with the Greek Κύφων , as described in the Scholia ad Aristoph. Plut. 476; the latter with the Roman Nervus (Plaut. Asin. 3 , 2, 5; Capt. 5, 3, 40), which admitted, however, of being converted into a species of torture, as the legs could be drawn asunder at the will of the jailer (Biscoe, On Acts, p. 229). The prophet Jeremiah was confined in an instrument of this sort ( Jeremiah 20:2), which appears to have been a common mode of punishment in his day (29:26; A.V. "prison"), as the prisons contained a chamber for the special purpose, termed "the house of the pillory" ( 2 Chronicles 16:10; A.V. "prison house").

2. סִד , Sad ( Job 13:27;  Job 33:11), which is expressly described as a fetter for the feet, and therefore perhaps answered to our Stocks.

3. עֶכֶס , Ekes ( Proverbs 7:22), was probably a fetter fastened round the ankle. The same word is used for an anklet ( Isaiah 3:18; A.V. "tinkling ornament").

4. צַינֹק , Tsinok ( Jeremiah 29:26), is, according to the Sept. and Vulg., merely a Prison, but is rather the Stocks proper, or some other confinement of the limbs; so Symmachus and the Hebrew interpreters generally (comp. the Arab Zanak, a fetter, and the root צָנִק , which seems to signify To Be Straitened ) .

5. The Ξύλον , literally Wood, to which Paul and Silas were made fast ( Acts 16:24) may have been " stocks" (as in Lucan, Tox, 29; Plato, De Genesis Socratis, 32), but was possibly simply a bar of wood to which they were chained by the feet. (See Prison).

What kind of stocks were used by the Jews, especially in the case of Jeremiah (as above), it is difficult to conjecture; whether they were encumbering clogs or fetters that did not absolutely prevent, but only embarrassed motion, or were fixed frames that kept the prisoner stationary. Both kinds were in use very anciently. The fixed kinds, properly called stocks, were of different sorts, being frames of wood with holes either for the feet only, or for the feet, the hands, and the neck at once. At Pompeii stocks have been so contrived that ten prisoners might be chained by the leg, each leg separately, by the sliding of a bar. Some of these forms of confinement particularly that which combined, in some sort, the pillory with the stocks were very painful, and are mentioned in the accounts of the sufferings of the early Christian martyrs (see Newman, Callista, p. 363. sq., where, however, the lignum of the Vulg. is confounded with the robur, or interior cell). (See Punishment).