ἀσαμίνθος appears only here in the Iliad, but ten times in the Odyssey (3.468 = 23.163, 4.48 = 17.87, 4.128, 8.450, 8.456, 10.361, 17.90, 24.370). Because it ends in –νθος, the word is generally taken to be a non-Greek word that has been adopted into the epic language (see Hainsworth 1993:210 ad 10.576 and Stanford’s [1961] commentary on the Odyssey ad 8.450). Hainsworth also notes that the word is attested on a seal from Knossos, and Stanford points out that earthenware bathtubs have been found at Knossos and Tiryns.
This line is the same as those found at Odyssey 4.48 and 17.87. The word ἀσαμίνθος is part of a formula system for getting in and out of the bathtub: eleven of its twelve appearances are part of a phrase that starts a line with ἔς ῥ’/δ’ ἀσαμίνθον/ἀσαμίνθους or ἔκ ῥ’/δ’ ἀσαμίνθου/ἀσαμίνθων and in most of these cases is followed by some form of βαίνω. So taking a bath in a bathtub is a frequent enough event in the epic tradition that this formula developed. The one exception to its line placement in the first two feet of the line is at Odyssey 4.128, which details the gifts that Helen and Menelaos received from Alkandre and Polybos in Egypt: Polybos gave Menelaos two silver bathtubs, among other things. Such a list of guest-gifts is, of course, a theme very different from narrating a hero getting in or out of a bath, and so it is not surprising that the formulas used are different in that case.
Getting in or out of the bath is more frequent in the Odyssey because it is associated with an arrival after a journey, which is a common occurrence in that epic. Telemakhos on his journey bathes at both Nestor’s palace (Odyssey 3.468) and at Menelaos’ (Odyssey 4.48, where it is both Telemakhos and Peisistratos bathing, and plurals are used as they are here). Odysseus gets in and out of the bath in the palace of Alkinoos and Arete (Odyssey 8.450–456) and tells of how he bathed at Circe’s once he had an oath from her for his safety (Odyssey 10.361). The association seen in that case between baths and safety appears many more times and is part of the poetics of the bath. Telemakhos (Odyssey 17.87–90), Odysseus (Odyssey 23.163), and Laertes (Odyssey 24.370) all bathe in an ἀσαμίνθος once they return home. Telemakhos has arrived safely after the suitors’ attempted ambush, and Odysseus bathes after his slaughter of the suitors: the baths, which involve an associated vulnerability of nakedness, signal safety after danger. Laertes is not so much in danger as in a prolonged state of suffering, and this kind of recovery has parallels elsewhere in the epic. Odysseus is of course known for his suffering on his journey, and he is given his distinctive epithet πολύτλας just before his bath in Phaeacia (Odyssey 8.446). In Odyssey 17, we have seen that Telemakhos’ bath implies safety after the danger of the suitor’s planned ambush, but his guest Theoklymenos bathes in that passage as well. Theoklymenos is an exile because he killed a man of his community (Odyssey 15.271–278), so Telemakhos taking him in is a measure of safety for him, and he is called here the “long-suffering guest” (ξεῖνον ταλαπείριον, Odyssey 17.84), a phrase used elsewhere of Odysseus himself (Odyssey 7.24; compare also Odysseus as a “long-suffering suppliant” ἱκέτην ταλαπείριον at Odyssey 6.193 and 14.511). Bathing in an ἀσαμίνθος, then, has associations with an arrival after a journey and with getting home safely after being in danger, and marks an end to suffering.
Bathing does indeed happen in other situations in the Iliad, but the word used in these other situations is λοετρόν (Iliad 14.6, 22.444–445, 23.44) or a related word (Iliad 18.346). We might expect the Trojans to bathe in their own homes, and we do see Andromache’s preparations for a bath for Hektor that he will never take (Iliad 22.444–445). But the Achaeans have hot baths as well, as we see when Nestor tells the wounded Machaon that Hekamede will prepare a hot bath for him and wash away the blood (Iliad 14.6–7) and when Achilles refuses the hot bath that Agamemnon ordered be prepared for him (Iliad 23.39–44). (Note that Achilles has also refused to eat since Patroklos’ death: as the following lines here also make clear, there is a thematic connection between bathing and eating a meal.) The corpse of Patroklos is also washed when it is brought back from battle (Iliad 18.343–353). There, we see in detail the water heated in a bathwater tripod, using formulaic language seen also when a bath is prepared for Odysseus in Phaeacia (Odyssey 8.435–437 ≈ Iliad 18.346–348). Similar to the way that Diomedes and Odysseus rinse and cool off in the sea here, we also see the Achaeans ritually wash in the sea after the end of the plague (Iliad 1.313–314). The Iliad thus displays several examples of other language about washing or bathing, and the language used here is particularly associated with journeys and ambush.
In a recent article, Jonas Grethlein (2007) examines the poetics of the bath in the Iliad. He confines his examination to the baths in the Iliad, saying that others have treated the theme in the Odyssey as part of the “ritual of hospitality,” which does not hold for the Iliad (2007:25). Grethlein argues for two types of baths in the Iliad: that of a warrior returning from battle (and he includes this bath in Iliad 10 in this category) and the washing of the corpse of a dead warrior (2007:28). Then he shows how these two types of bath create narrative tensions and connections, focusing especially on the bath that Andromache prepares for Hektor (2007:28–49). Grethlein also argues that both kinds of bath share a connection with a transition: the bathing of the corpse involves the transition from life to death, and the warrior’s bath involves a transition from the danger of death in battle to a place of safety (2007:28–29). Our arguments about the bath here in Iliad 10, developed before Grethlein’s article appeared, agree in many ways with his. But in his separation of the Iliad and Odyssey, he seems to have overlooked that the arrival after a journey, beyond being simply hospitality, often in the Odyssey includes a similar measure of safety after danger as that which he sees in the warrior’s return from battle in the Iliad. And although he pays close attention to formulaic language in these types scenes, he does not mention the particular language used in this case, which differs from the other baths in the Iliad in particular ways.
We can now see what ἀσαμίνθους adds to this particular scene. This type of bathtub is formulaically associated with the safe arrival from a journey, and a night mission, whether spying or ambush, is thematically like a journey particularly in that it involves a return. We have seen (1) Nestor describe the spying mission as (ideally) a going out and coming back safe and sound (see 10.211–212), (2) Diomedes choose Odysseus as his partner for the mission because of his abilities to get home (10.247), and (3) Athena tell Diomedes to remember his homecoming while he lingers momentarily in the Thracian camp (10.509). As Albert Lord notes briefly regarding the bath Odysseus takes in Odyssey 23: “The bath belongs in the tale of the return—it surely has ritual significance” (1960:176). There is an idea of a nostos associated with this kind of mission, and the traditional association of a bath in a tub with a safe arrival after a journey appears in this expanded version of the spying/ambush theme.