Your Spirit is your essence, your superconsciousness, your Soul or Being. The more you develop the Spirit the more unified you will feel. You may call it approaching Oneness, detachment of Ego, becoming the ultimate observer, enlightenment or spiritual awakening. You may also describe it as a feeling of an invisible force that operates behind the scenes of what we Experience. Something that is larger than us.
"It is through Gratitude for the present moment that the spiritual dimension of life opens up."
Eckhart TolleEXERCISES CHAPTER 1: FOCUS YOUR PURPOSE