Quick Definition
poison, rust
Strong's Definition
rust (as if emitted by metals); also venom (as emitted by serpents)
Derivation: perhaps from (to go) or (to send);
KJV Usage: poison, rust
Thayer's Greek Lexicon
ἰός, ἰοῦ, ὁ (on its very uncertain derivation see Kreussler in Passow, under the word; Curtius, § 591; (Vanicek, p. 969));
1. poison (of animals): ἰός ἀσπίδων ὑπό τά χείλη αὐτῶν, the poison of asps is under their lips, spoken of men given to reviling and calumniating and thereby injuring others, Rom_3:13 (from Psa_139:3 ()); by the same figure, (γλῶσσα) μεστή ἰοῦ θανατηφόρου, Jas_3:8; (in Greek writings from Pindar down).
2. rust: Jas_5:3; (Eze_24:6; Eze_24:11 f; Bar_6:11; Bar_6:23 (Epistle Jer_12:1-17; Jer_24:1-10); Theognis, Theocritus, Plato, Theophrastus, Polybius, Lucian, others).
Mounce Concise Greek Dictionary
ἰός ios 3x
a missile weapon, arrow, dart; venom, poison, Rom_3:13 ; Jas_3:8 ; rust, Jas_5:3
Abbott-Smith Greek Lexicon
ἰός , -οῦ , ὁ ,
[in LXX : Eze_24:6 ; Eze_24:11-12 ( H2457 ), Psa_140:3 ( H2534 ), al. ;]
1. an arrow.
2. rust (Ez, l.c .): Jas_5:3 ( cf. MM , Exp., xv).
3. poison: fig ., Rom_3:13 (Ps. l.c .), Jas_3:8 .†
Moulton & Milligan — Vocabulary of the Greek NT
ἰός [page 305]
Syll 587 .810 (B.C. 329) σίδηρος καταβεβρωμένος ὑπὸ τοῦ ἰοῦ illustrates the special sense of rust, found in Jas_5:3 : cf. ib. 139 .15 (iii/B.C.) ὅπως δὲ καθαρὸς [ἰ ]οῦ ἔσται ὁ ἀνδρίας . . . ἐπιμελεῖσθαι τοὺς ἀγορανόμους . The more general sense is seen in P Tebt II. 273 .16 (ii/iii A.D.) ε̣ἰοῦ Κυπρί [ου ] (δραχμὴ ) ᾱ , similarly .37 , in medical prescriptions for the eyes.
As against Grimm s very uncert. deriv. the word is obviously cognate with the Latin virus (Zend viš , v̯ ša , skr. višam : see Boisacq, p. 379).
STEPBible — Tyndale Abridged Greek Lexicon
ἰός, -οῦ, ὁ
[in LXX: Eze.24:6, 11-12 (חֶלְאָה), Psa.140:3 (חֵמָה), al. ;]
__1. an arrow.
__2. rust (Ez, l.with): Jas.5:3 (cf. MM, Exp., xv).
__3. poison: figuratively, Rom.3:13 (Ps. l.with), Jas.3:8.†
(AS)
📖 In-Depth Word Study
Poison (2447) ios
Poison (2447) (ios from hÃemi = to send) is something sent out and one Greek meaning is thus arrow, a meaning not found in the NT.
Ios is used in the NT to mean poison or venom. The idea is something that is emitted since venom is ejected or emitted from a serpent's fangs. Ios also means rust as if emitted by metals.
Ios is used 3 times in the NT (see below) and 7 times in the (Ps 14:3; 140:3; Pr 23:32; Lam 3:13; Ezek 24:6, 11, 12)
James uses ios with both meanings (poison and rust) writing...
(James 3:8) (Describing the Tongue James says that) "no one (Greek = absolutely no one. Have you ever tried?) can (dunamai = have power by virtue of inherent ability and resources) tame (reduce to stillness or quietness) the tongue; it is a restless (Unsettled, unsteady, unstable, staggering, reeling like a drunken man. Not having stability) evil and full of (replete, stuffed) deadly (literally death bringing) poison (ios). (James 3:8) (Comment: The tongue of an unregenerate man or even of a believer not controlled by the Spirit is like a deadly poisonous snake. The venomous evil chafes at confinement, always seeking a way to escape and to spread its deadly poison. This "poison" is more deadly than a snake's because it can destroy morally, socially, economically, and spiritually.)
(James 5:3) (Warning the materially rich James writes) Your gold and your silver have rusted; and their rust (ios) will be a witness against you and will consume your flesh like fire. It is in the last days that you have stored up your treasure! (Comment: Here rust is a warning against heaping up worldly wealth. The rust will not merely rot this but will serve as a testimony against its owners and sear their flesh like fire. The point is not just that rust proves the transitoriness of riches but that it accuses the rich for letting things rot rather than give them to the poor!)
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