At the deepest level of esoteric meaning, the two represents the conscious mind and the subconscious mind; the light and dark side of your character - that which is known and that which is unknown.
Ancient cultures were aware of this duality in people. Indeed they knew duality existed in everything from the smallest sub-atomic particles to the vastness of the Cosmos.
The same is true for mankind, reflected by the idea of the microcosm (man) and the macrocosm (the universe). Jung alluded to this from a psychological perspective by differentiating the unconscious between the personal mind (the subconscious) and the Collective Unconscious (the Universal Mind or Akasa etc.)
You will find Jung's inspiration for his theory of the Unconscious in ancient myth, even the earliest writings.
For example, in Zoroastrian traditions which date back to the 6th-Century BCE, we find that Ormuzd and Ahriman are both emanations from one being. Ahriman and Ormuzd, share a co-eternal existence and both are emanations from one source. Ormuzd represents nature that is good, and Ahriman is the opposite aspect of evil. These are the two expressions of one and the self-same essence.
Nothing can exist without a reflection or alternative outcome. In terms of the polarity in humans, it is up to you as an individual to control your dual natures and do only that which is right in the right moment.
That’s not to say, you should always do good as the Church wants us to believe. The “Seven Deadly Sins” are not wrongdoings, they are aspects of human nature which bring satisfaction, happiness and growth.
What is important to remember is balance. There has to be a balance between vices and virtues.
Balance is simply a Truth of Nature; a natural law that determines whether a system maintains equilibrium. Systems that suffer an imbalance become unhealthy.
The principal symbol of every organised religion in the world represents balance. Just saying.
For mankind, our reality is created through thoughts, emotions and actions. The number two is the union of thoughts and emotion which prompt action - number three.
If you want something enough, act upon your desires to make them manifest.
Whereas the one is putting thoughts into action, number two is a signal to start planning. This often starts by looking within and asking your higher self, what to do next.
The two represents male and female energies that bring about balance and can sometimes call for us to make a choice as we see in the card of the Lovers in the Tarot – a card with astrological meanings relating to the house of Gemini.
The number Two also symbolises the need for kindness, tact and nurturing. It may appear to you when exchanging deals in partnerships whereby communication is key. The symbol may be telling you to exert your natural flow of judgment to do what is best for your soul.
The Universe is a mass of energy – and so are you. It stands to reason therefore that you can tap into that energy. Ancient cultures all over the world have known this for thousands of years and today science is exploring the idea to find physical evidence to explain how it works.
The ancient mystery schools say we are one with the Universe and can access whatever information we need by learning how to connect with the Higher Self – an aspect of the unconsciousness that is not yet known to the conscious mind.
It is written in the Kybalion that:
“He who grasps the truth of the mental nature of the Universe is well advanced on the path of mastery.” ~ The Kybalion
The idea is described, as above, so below in Hermetic writings, which among other things, means the energy you project will return as a manifestation in the material world. Therefore, we must pay attention to our thoughts, emotions because the actions we perform transform energies that manifest in your life.
If the number two keeps showing itself to you, consider pursuing your ideas further, start planning and put your ideas into action. You should also take note of your thoughts and emotions. At other times, the two may be a reminder for you to be thoughtful and sensitive towards others.