The question, “Is yoga a religion?” is not only a fair one to ask, but a good question to understand. The answer is “No”.  Yoga offers no dogma; it is a science that shares tools, and variations of practice to use those tools to go inward into ourselves.

Because its roots are in India, many people confuse Yoga with Hinduism or Buddhism, two well-known religions in India (although Christianity, Judaism and Islam are prominent as well – http://en.wikipedia.org/wiki/India).

Yoga is a tradition originating from the East and originally this science was predominately practiced there; but just as practicing meditation will not cause or encourage one to become Buddhist, and praying will not cause or encourage one to become Christian, practicing yoga will not cause or encourage one to become Hindu or any other religion.

If you look into it, one will find that that religion and yoga are very different.  In general, Yoga is missing many things that are usually part of religions:

Yoga has no deity to worship.
Yoga has no worship services to attend.
Yoga has no rituals to perform.
Yoga has no sacred icons.
Yoga has no creed or formal statement of religious belief.
Yoga has no requirement for a confession of faith.
Yoga has no ordained clergy or priests to lead religious services.
Yoga has no institutional structure, leader or group of overseers.
Yoga has no membership procedure.
Yoga has no congregation of members or followers.
Yoga has no system of temples or churches.

Yoga is a science and an art, that offers tools and a practice for a healthy, balanced body and a clear mind.  Yoga is a practice of mindfulness, of observation, that allows us to live in clarity and find our own personal truth.  Whether that truth is found in one’s religion or just in one’s heart, does not matter to Yoga.

From a teacher and practitioner standpoint, I encourage every person reading this to ask these types questions and to find out for oneself.

For deeper exploration on this subject, here are a few links to check out:

http://www.swamij.com/religion.htm#useful
http://www.yogajournal.com/lifestyle/283
http://yoga.about.com/od/yogafa1/f/yogareligion.htm