Kriya Yoga is the scientific art of perfect God-Truth Union.

To live and act totally consistent to action with the awareness of what is signified by Yoga is called 'Kriya Yoga'.

Kriya means action, and Yoga means citta-vritti-nirodha : Citta (mind), Vritti (ideas), Nirodha (control).

The process is control of ideas in the mind to contemplation; through discrimination to spiritual independence.

Tapa (penance), Svadhyaya(self-study), Isvarapranidhana (devotion) together form Kriya Yoga.

Kriya Yoga is not a matter of doing but of being aware of everything that one may be doing.

Paramahansa Yogananda was born Mukunda Lal Ghosh on January 5, 1893, in Gorakhpur, India.

In his youth he sought out India's sages, hoping to find an illumined teacher to guide him in his spiritual quest.

At age 17, Yogananda met and became a disciple of Sri Yukteswar Giri.

He spent the next ten years, receiving Sri Yukteswar's spiritual discipline.

After Yogananda graduated from Calcutta University in 1915, he took formal vows as a monk of India's venerable monastic Swami Order, where he received the name Yogananda (signifying bliss through divine union).

In 1917, he founded a boys school, where modern educational methods were combined with yoga training and spiritual instruction. Mahatma Gandhi wrote: "This institution has deeply impressed my mind."

"Do not think that you can comprehend the Infinite Lord by reason.....Man's highest faculty is not reason but intuition: apprehension of knowledge derived immediately and spontaneously from the soul, not from the fallible agency of the senses or of reason."

In 1920, Yogananda was invited to serve as India's delegate to an international congress of religious leaders convening in Boston.

That same year he founded Self-Realization Fellowship to disseminate worldwide his teachings on India's ancient science and philosophy of Yoga.

Over the next decade, he traveled and lectured widely, speaking of the underlying unity of the world's great religions, and taught universally applicable methods for attaining direct personal experience of God. To serious students of his teachings he introduced the techniques of Kriya Yoga.

In 1935, he toured Europe and India. During his year-long sojourn in his native land, he spoke throughout the subcontinent and enjoyed meetings with Mahatma Gandhi (who requested initiation in Kriya Yoga).

During this year, Sri Yukteswar, bestowed on him India's highest spiritual title, Paramahansa - the title signifies one who manifests the supreme state of unbroken communion with God.

On March 7, 1952, Paramahansa entered mahasamadhi, a God-illumined master's conscious exit from the body at the time of physical death.

Like Gandhi, Yogananda writes humbly and includes his foibles and the pratfalls he takes as he journeys through life's lessons. In fact, unless you read elsewhere about his life you won't realize how much he understates his own accomplishments while he honors other spiritual seekers and teachers he encounters.

His stories of encounters with amazing saints of all regions and religions are spell-binding, and you may find yourself (like me) devouring the whole book on your first read -- just reveling in the wonders of these true spiritual seekers.

On successive readings I delved deeper into the equally fascinating footnotes, learning about the exotic realms of Indian spirituality and its unexpected parallels with the original Christian teachings of Christ, St. John, and St. Paul. In fact, the countless strata of insights and implications that surface with repeated readings of Autobiography of a Yogi.

In all my reading in spirituality, yoga, and comparative religion, I have discovered no work that so completely fulfills Carl Jung's prophecy that yoga science (the whole science, not just the asana postures) will offer you ''undreamed-of possibilities'' as Yogananda's autobiography.

As the author explains, 'yoga' comes from the root meaning 'union' - and he reveals, ever more deeply, the underlying oneness of Christianity and yoga, of spiritual truth and scientific truth, of the worldly and the spirituality. It will deepen anyone's own faith and sensibility -- of whatever religion (or none), of the science of matter... or mind... or Spirit.