Like any true and powerful ancient symbol, Icovellavna(name of this pattern and weaving), has many interpretations and layers of interpretation accessible to the minds of initiates. Firstly, at the microcosmic level, our soul/body is a connection between “all worlds”, that is, the physical, astral and mental. This is also the ligature of three granthas, knots that need to be untied for the safe ascent of Kundalini. The unification of three “layers” and levels of the soul around is Kundalini, which closes them all together and gives complete knowledge and the ability to understand “every world.” This is at the microcosmic level.
More mystical explanations about the connection between the three worlds and the Elinistic Three Gods-rulers of the worlds (Zeus, Poseidon, Hades). I don't know Celtic mythology very well, but I'm sure that a similar motif is also present in their Pantheon. Circle - Solar symbolism, and at the same time an indication of the conscious principle. Within the circle, all three worlds can be comprehended and interact with each other.
In Slavic paganism, there is a similar motif expressed as “three worlds”, Yav, Nav and Prav. Despite the fact that this reflects many levels of interaction between our consciousness and soul. For example, Yav can be associated with the left hemisphere, Nav with the right, and Prav with the superconscious.This also, according to the Hermetic maxim (as above, so below), has external analogies in the structure of the world. Yav as manifested, what we have as solid ground under our feet, Nav is the world of dreams, the unmanifested/astral. And Prav like a super reality.
In India, there is a teaching that Mahadev, as the root cause of existence, rules the world using the Three Gunas - Tamas, Rajas and Sattva. And again, this has both external and internal meanings. The relationship of the three through something 4 - the power of the Snake, Ouroboros, gives us an understanding of the complexity of this pattern. While studying the Nath tradition, I came across a symbolic explanation of what the symbolism of the “three rings of Kundalini” means, and I think, like all the triplets described above, this relates to this topic. The three revolutions symbolize the three states of consciousness: waking, dreaming, and deep sleep. The rise of the Snake in this symbol is expressed as 4, the achievement of Samadhi and Superconsciousness.