halusis

The lexicons are unanimous about the sense. BDAG (3rd ed., s.v. ἅλυσις) defines it as a chain or bond used for restraint and notes the specialized use for the handcuff by which a prisoner in Roman custody was fastened to his guard; LSJ (s.v.) documents the ordinary Greek usage from Herodotus onward, including ornamental chains, a use the New Testament never has. The derivation is uncertain: the popular analysis as an alpha-privative compound of λύω, "what cannot be loosed," is not accepted by the etymological lexicons, and Chantraine (Dictionnaire étymologique de la langue grecque) and Beekes (Etymological Dictionary of Greek) treat the word as of obscure, probably pre-Greek origin. For the custody background behind Acts and the Prison Epistles, Brian Rapske, The Book of Acts and Paul in Roman Custody (BAFCS 3, 1994), sets out the practice of chaining a prisoner to a soldier (custodia militaris, military custody) and its bearing on Acts 12:6, 21:33 and 28:16-20; C. K. Barrett (ICC, Acts, vol. 2) and Craig Keener (Acts, vol. 4) discuss the force of Paul's demonstrative "this chain" at Acts 28:20, where the chain is at once the object he can point to and shorthand for the case that brought him there. On Ephesians 6:20 Ernest Best (ICC, 1998) and Harold Hoehner (Ephesians, 2002) read the phrase as a literal reference to the writer's custody that simultaneously sharpens the ambassador image, since an ambassador in chains is a contradiction in Roman terms. At 2 Timothy 1:16 the singular is generally taken as metonymy for the imprisonment as a whole (I. Howard Marshall, ICC Pastoral Epistles, 1999; George W. Knight III, NIGTC, 1992). In the Septuagint the word renders both ornamental chains and prisoners' fetters, so the exclusively restraining usage of the New Testament represents a narrowing of the term's range.