The two dimensions, the spiritual and the material, are like the two wings of a bird or the two legs of a human being. Both wings are necessary for birds to fly. In order to walk, both legs are necessary. If you try to walk on only one leg, you will stagger and fall. This need for the material and spiritual dimensions has been explained in yogic philosophy.
Yoga does not denounce the material or the physical aspect, yet at the same time, it informs and warns everyone that materialism without spirituality leads to suffering, and spirituality without material fulfilment leads to dissatisfaction. Therefore, the yoga inherent in our vedic and tantric traditions has stated that every individual who wishes to excel in life and develop his intellect, talents and brilliance must not only consider the material, physical, extroverted self, but also the internal, spiritual self. It is only then, that with the practices of yoga we can attain physical health, mental harmony and spiritual realization. It is for this purpose that the seers and sages of ancient India developed the science and the metaphysics of yoga. Let me remind you that yoga is not only a group of practices that you do to alleviate yourself from physical disorders and obtain mental peace. It is not a collection of techniques that lead you to self-realization. It is a balanced lifestyle where you are aware of the values of human life and express them creatively and constructively.