yoga philosophy
bhagavad gita 2.20
    he word 'yoga' comes from the sanskrit root 'yuj' and means: to join, to connect or to unite. This idea that yoga involves a union, is even conveyed in yoga's English language cognates (e.g., the word "yoke"). When you speak of "yoking" oxen to a plow, by that act you're connecting the ox to the plow, and thereby bringing the two things together.
In yoga, we seek to connect our individual consciousness with the Absolute Truth. This is the fundamental aim of yoga and the primary message of the Bhagavad Gita (Song of God). This 700–verse Hindu scripture is nestled in the middle of the ancient Sanskrit epic, the Mahabharata.  It is a two hour conversation between Arjuna (a great warrior), and Krsna (his charioteer and guide) who is revealed throughout the course of the discussion to be God incarnate. The teachings revealed in the Gita touch on every dimension of the human condition. Weather one is a beginner to spirituality or an advanced practitioner, there is a verse that will offer one guidance in whatever one may be seeking.
Faced with the ultimate conflict, fratricidal war, a bewildered Arjuna turns to his friend Krshna for counsel on the battlefield. Krshna then imparts to Arjuna, the wisdom of yoga. The first teaching we receive from Krsna is that we are not the body. Sometimes we think we are the body, but we are not the body. We are a soul with a body which serves as a vehicle for Self-realization. This realization serves as the substratum that will liberate Arjuna from experiences of doubt, fear and worry in the temporary material existence that is constantly changing. Like everything in this material world, our body with every breath, is constantly changing. The soul, however, does not change.
Yoga is a journey, through which we explore and discover the power within ourselves. We use the sword of knowledge to slash away the impurities that prevent us from uniting with our Source. The practice of yoga helps us recognize the basic problem, which is ignorance; a confusion regarding the distinction between Self and the non-Self. As we establish ourselves in yoga, we tap into a reservoir of unleashed potential and in time, everything that is not authentic is cut away.
There is a sacred Indian chant that helps one to realize that we should honor the gift of existence, by having gratitude for all of life's growth opportunities (even the experience of suffering, which is often a precursor to the greatest advancements); to realize that we must open ourselves up to a heightened awareness (one that transcends the limited confines of our own mind), so we can move physically, mentally, emotionally and spiritually to higher planes of consciousness.
"A mantra is mystical energy encased in a sound structure and each mantra contains within its vibrations a certain power. But of all mantras, the maha-mantra (the Hare Krishna mantra) has been prescribed as the easiest and surest way for attaining God Realization in this present age." ~ George Harrison (1943-2001) 
bhagavad gita 4.42
Therefore O Arjuna, by the sword of transcendental knowledge destroy these doubts of the self, born of ignorance, situated in the heart and taking shelter of the science of uniting the individual consciousness with the Ultimate Consciousness arise for battle.
For the soul, there is neither birth nor death at any time. It has not come into being, does not come into being, and will not come into being. The soul is birthless, eternal, imperishable and timeless and is never destroyed when the body is destroyed.