Pillars, cosmologically, represent the supports of a spiritual principle.
The pillars of the earth at the cosmic scale are usually depicted as opposites, like the pillars of Yakin and Boaz, in order to express the maximum range of implication. Opposites are the most different expressions possible, and they always provide the best support for knowledge. Opposites frequently appear in ancient symbolism.
(The Language of Creation: Cosmic Symbolism in Genesis - A Commentary by Matthieu Pageau, 2018. Pages 43-45)