Adam,Eve and the snake.
Human ,god and holy Ghost
Jesus,father and spirit

Greek goddess in the form of three faces. which was recognised by carl yung throughout the world in every religion the same thing in different characterization. So he called it archetypes. These are talking the same things through different metaphors.

In the middle vishnu unites the duality(being and nonbeing, moral immoral, light darkness ,human-god, masculine -feminine,consciousness-unconsiousness, male-famale). Without duality , we can’t even think, we can’t even experience.there is no space time, in the middle something that plays the shadow game with two. Which is associated with eternity.from there both aspects came out. Like in middle singularity from there ,duality comes out .(big bang theory).

There is a Hindu emage that shows a triangle, which is the mother Goddess,and a dot in Centre of the trangle.which is energy of transcendental entering the field of time.and then from this traingle there comes pairs of triangle in all directions.out of one comes two.

Same way..
Shiva source of transcendental energy.
engaged into the Field of time which is represented by Goddess (Parwati) genital creates the universe.all the duality comes out.