What is the best manner to translate the 1 Sam 5:4’s expression (רק דגון נשׁאר עליו), commonly translated in two different manners, that is (a) ‘the stump (or, ‘base’, ‘trunk’) of Dagon’ [NAB, NASB, NRSV, NLT, and so on], or (b) ‘the fish (or, ‘fishy’) part’, ‘fish portion’ [Rashi’s Commentary, Isaac Leeser, Darby, Young, NWT]?
From the Bible account itself we learn that this idol included two main parts. In fact, if we translate literally the expression at issue we have: “only (or, ‘but’) Dagon [had been left (or, ‘remained’) upon him]”. Then, the ‘head’ and the ‘hands’ (that is, the superior anthropomorphic part of the idol), weren’t the distinctive characteristics of Dagon. Instead, according the Bible account, was the inferior part of the idol the distinctive section of that god, so to call it “Dagon”.
First of all, I would cite some commentators (bold is mine).
Treasury of Scriptural Knowledge (TSK, 1834), ad locum (bold is mine): “The name of this idol, Dagon, signifies a fish, and it is supposed to be the Atergatis of the Syrians, corruptly called Derceto by the Greeks, which had the upper part like a woman, and the lower part like a fish; as Lucian [in his De Dea Syria] informs us: ‘Δερκετους δε ειδος εν Φοινικη εθεησαμην, θεημα ξενον; ημισεη μεν γυνη; το δε οκοσον εκ μηρων ες ακρους ποδας, ιχθυος ουρη αποτεινεται’, ‘In Phoenicia I saw the image of Derceto; a strange sight truly! For she had the half of a woman, but from the thighs downward a fish's tail.’ Diodorus (1. ii.) describing the same idol, as represented at Askelon, says, το μεν προσωπον εχει γυναικος, το δἀλλο σωμα παν ιχθυος. ‘It had the head of a woman, but all the rest of the body a fish’s.’ Probably Horace alludes to this idol, in De Art. Poet. 4; ‘Desinat in piscem, mulier formosa superne’, ‘The upper part a handsome woman, and the lower part a fish.’ If such was the form of this idol, then everything that was human was broken off from what resembled a fish.”
Joseph Benson (Commentary on the Old and New Testament, ad locum), mentioning Kimchi: “[…] that is, saith Rabbi Kimchi, that part of it from which it was called Dagon, namely, the fishy part; for dag [דג], in Hebrew, signifies a fish.”
Benjamin Davidson (Analytical Hebrew and Chaldee Lexicon) defined the term here (דגון) as “large fish”.
John Parkhurst (A Hebrew and English Lexicon […], on דג): “From 1 Sam. V. 4, […] it seems that this idol resembled a fish in the lower part, with a human head and hands […]. ‘Piscem Syri venerantur’, ‘the Syrians worship a fish’, says […] Cicero [in] De Nat[ura] Deor[um], iii cap. 15.”
Nevertheless, several scholars think Dagon is a derivative from the term ‘dagan’ (grain), so interpret Dagon as a fertility-, or, agriculture-God.
Half-Jokingly: If the theonim ‘Dagon’ is a derivative from ‘dagan’ (grain) – as someone thinks - may we imagine this god like a huge wheat ear? In this case, how the inferior part of the spike – the stem - could represent a distinctive characteristic of Dagon?
Seriously: If the theonym ‘Dagon’ is a derivative from ‘dagan’ (grain) – as someone thinks - may we imagine this god as a Demeter-like divinity embracing a corn shock (really, you may see this historical representation of this goddess in a lot of shots in the WEB)? But, if this is the case, how – again - the inferior part of a Demeter-like divinity could represent a distinctive characteristic of Dagon?
We may walk along through a better way if we embrace one of the hypothesis yet mentioned, that is, that Dagon comes from ‘dag’ [דג] (fish), since we know the historical existence – in ancient times – of the god Dagon (or, Odakon), or his homologues gods. Even if in other traditions this divinity was called differently (for one example, ‘Oannes’), the prerogatives and characteristics were identical to those of Philistine Dagon (who is an expert in mythology – being able to compare god pantheons of several ancient people - does know this elementary homologative tendency). In every case, this god (Dagon) was formed by a human (male or female) superior part, and a peculiar inferior part that represented always a final part of a fish.
In an essay of him, Robert Temple (The Syrius Mystery) wrote: “The main individual of the group of amphibians is called Oannes. […] There are several illustrations of him throughout this book (Plates 6, 7, 8 and 9 and Figures 30 and 31). In somewhat later traditions than the ones Berossus drew on, Oannes became the fish-god of the Philistines known as Dagon and familiar to many readers of the Bible. […] in the Berossus fragments preserved by the historian Apollodorus, we read that ‘there appeared another personage from the Erythraean sea like the former, having the same complicated form between a fish and a man, whose name was Odacon’. This seems fairly clearly to be a corrupted form of ‘Dagon’. Unless ‘Dagon’ is a corrupted form of ‘Odacon’.” (pp. 206-207)
On the plates and figures cited by this author we find various some homologous divinities of this Dagon-kind, like Nereus, on a Greek ceramic-painting; Skylla, on a ceramic-painting; Dagon/Oannes, on a Etruscan amphora’s ceramic-painting; various Oannes as a huge statue, statuettes, and on some Assyrian cylindric seals).
Last but not least, a extraordinary coincidence (?). A famous African tribe believe that their civilization was founded by amphibian individuals, with tails of fish… The name of the tribe? DOGON.
So, it was the fishy part of the idol the characteristic of that god. For this reason the Bible called this part ‘Dagon’. Consider: aside several Egyptian gods, the divinities of the other people were – in vast majority – modelled on the anthropic physical structure (man/woman). So, the ‘humanized’ part of a god (common to the majority of divinities representations) hardly possessed the specificity linked with a given god. For one example, the physical form of a Greek Zeus statue was not bodily different from a Poseidon statue. What distinguished the two characters were some non-human factors, like the bundle of lightnings in the hand of Zeus, or the wielding of a trident, in case of Poseidon.
Granted, the translation ‘trunk’, ‘spine’, ‘backbone’, by LXX; and ‘truncus’ (see how from this term comes the English ‘trunk’) by Vulgate, isn’t altogether incorrect. In fact, any form possessed the inferior part of the idol served as – in every case - a trunk, or stump, of Dagon’s statue. Nevertheless, the LXX/Vg’s (and the like) way to translate triggers a loss of the original term’s specificity. In linguistic terms, those translators did choose – in these cases – to broad the semantic field (or, area), or, in other words proceeding from a more specific term to a more generic term. Regrettably, this is the common (and, sorry, sometimes inevitable) manner to translate a term, but only when we do not know the exact meaning of it. Probably, this factor (that is, the lack of knowledge – in those ancient epochs - of the exact meaning) urged the LXX/Vg (and the like) to translate so.
However, I think we – today - are able to improve our translation of this particular passage, restoring the specificity of the original term, because now we possess an increased knowledge of ancient mythologies, compared to the LXX/Vg’s compilation times (through the several archaeological discoveries of ancient libraries of thousands clay tablets, which inform us about ancient god and mesopotamic goddesses; along with discovered reliefs/statues which illustrating the form of those ancient divinities. I think – for example – the discovered libraries of some mesopotamic city-state, like Ebla, Nineveh, and so on; or the ‘Dagon’ relief found by Austen Henry Layard in the 19th century).
All thing considered, I think reasonable to conclude that the better manner to translate this expression is: “only (or, ‘but’) the fishy part [of Dagon] had been left (or, ‘remained’) upon him”.
This ubiquitary ancient divinity was so famous (and worshipped) that IEUE warned his delivered-from-Egypt people, with the words we find in Deuteronomy 4:18: “You saw no form of any kind the day the LORD [יהוה] spoke to you at Horeb out of the fire. Therefore watch yourselves very carefully, 16 so that you do not become corrupt and make for yourselves an idol, an image of any shape, whether formed like a man or a woman, 17 or like any animal on earth or any bird that flies in the air, 18 or like any creature that moves along the ground or any fish in the waters below.” NIV