6398. 'Dan will be a serpent on the road' means their reasoning regarding truth, since good does not as yet lead them. This is clear from the representation of 'Dan' as those guided by truth but not as yet by good, dealt with above in 6396; from the meaning of 'a serpent' as reasoning based on sensory evidence, dealt with below; and from the meaning of 'the road' as truth, dealt with in 627, 2733. Thus 'Dan is a serpent on the road' means their reasoning regarding truth, since good does not as yet lead them. The nature of that reasoning and the nature of the truth resulting from it will be stated below.

[2] The reason why 'a serpent' means reasoning based on sensory evidence is that the interiors of a person are represented in heaven by living creatures of various kinds, and therefore in the Word similar things are meant by those same creatures. A person's sensory powers have come to be represented by serpents because they are the lowest of his mental powers. Compared with other mental powers those of the senses are on the ground so to speak, crawling around there, as may also be recognized from the forms that sensory impressions adopt when they enter in, which will in the Lord's Divine mercy be dealt with elsewhere. This explains why those sensory powers have come to be represented by 'serpents', so much so that the Lord's Divine sensory perception was represented by the bronze serpent in the wilderness, 4211 (end).

[3] True shrewdness and circumspection - qualities that reveal themselves in external affairs - were also meant by 'serpents', in Matthew,

Be shrewd as serpents and simple as doves. Matthew 10:16.

But in the case of a person who is governed by his senses and is far removed from what is internal - as those people are who are guided by truth but not as yet by good - and who speaks as his senses tell him, 'a serpent' means false reasoning. This therefore is why here, where Dan is the subject, reasoning regarding truth because good does not as yet lead him is meant. In other contexts ill-will, deceitfulness, and trickery are also meant by 'serpents', though in those places they are poisonous serpents - such as vipers and the like - whose reasoning is their poison.

'A serpent' is reasoning based on sensory evidence, see 195-197.

'A serpent' is all evil in general, and evils are distinguished from one another by different kinds of serpents, 251, 254, 257.

257. 'The head of the serpent' is used to mean the reign of evil in general and of self-love in particular. This becomes clear from its very nature, which seeks not merely to exercise dominion but also to exercise it over everything on earth. Yet it is not satisfied even with that, but seeks to rule over everything in heaven. Nor is it satisfied even then, but seeks to rule over the Lord. And even then it would not be content. This inclination lies concealed within every spark of self-love. If it were shown the slightest approval and the restraint on it were slackened, you would perceive it break out instantly and strive increasingly to achieve that end. From this it is clear how 'the serpent' or evil constituting self-love wishes to have dominion, and how it hates the person it is unable to dominate. This is 'the serpent's head' which rears itself and which the Lord treads on, right down to the ground so that it goes on its belly and eats dust, as described in the previous verse. The serpent or dragon called Lucifer is similarly described in Isaiah,

Lucifer, you said in your heart, I will go up the heavens, above the stars of God I will raise my throne, and I will sit on the mount of assembly, in the uttermost parts of the north. I will go up above the heights of the clouds, I will make myself equal to the Most High. But you will indeed be cast down to hell, to the sides of the pit. Isaiah 14:13-15.

The serpent or dragon is also described in Revelation,

A great fiery-red dragon having seven heads and ten horns, and on his heads many jewels; but he was cast down to the earth. Revelation 12:3, 9.

This describes the height to which it raises its head. In David,

Jehovah said to my Lord, Sit at My right hand until I make Your enemies as Your foot-stool; Jehovah will send the rod of Your strength from Zion. He will judge the nations, He will fill them with corpses. He has crushed their head over much land. He will drink from the stream by the way, therefore He will lift up his head. Psalms 110:1-2, 6-7.