The 3 vehicles - Theravada, Mahayana (Great Vehicle) &
Vajrayana (Diamond Vehicle) are similar in essence, and differ in
terms of how the Dharma is being packaged - e.g. difference in
monks' robes, areas of emphasis & practice methods.
Like a cup of tea (Dharma) may be placed in a golden cup, a teacup,
a glass, or a triangular-shaped cup, the external shape (practice
methods) may seem different, but the inner essence (tea, i.e.
Dharma) remains the same.
Theravada, sometimes we refer to it as Buddhism transmitted from
the Southern Route (nan2 chuan2 fo2 jiao4). It spread from India to
most parts of Southeast Asia, like Thailand, Myanmar, Laos, Sri
Lanka, Vietnam, Singapore, Malaysia. The emphasis of practice is
generally on observing strict precepts and the goal is to attain
Arahantship, by extinguishing the conditions (eg. greed, hatred,
ignorance) for continued Samsaric existence. There is usually a
strong tradition of Shamatha (concentration) and Vipassanna
(analytical/insight) meditation.
Mahayana is sometimes referred to as Buddhism transmitted from the
Northern Route (bei3 chuan2 fo2 jiao4). It spread to places like
China, Japan, Korea, Vietnam, Singapore, Malaysia. The emphasis of
practice is generally on the 6 Perfections (Perfection of
generosity, morality, patience, joyous effort, concentration,
wisdom). The goal is to attain Buddhahood, for the sake of
benefiting all sentient beings (also referred to as Bodhicitta).
Besides Buddhas, Mahayanists also believe in Bodhisattvas, who
appear in the world so as to benefit sentient beings. It is said
that one needs to practice the 6 Perfections as a Bodhisattva for 3
countless aeons, in order to become enlightened. Examples of
Mahayana traditions include Pureland, Zen, Chinese Ch'an, Hua Yen,
etc.
Vajrayana is actually a branch of Mahayana. It also has a very
strong emphasis on Bodhicitta. In fact, the sense of urgency in
wanting to benefit all sentient beings is so great that a Vajrayana
practitioner wants to quickly attain enlightenment. As such, they
use extremely efficient methods that could allow one to attain
enlightenment very quickly (in some cases, within one lifetime).
However, it is said that when it's faster, the practice is more
dangerous - dangerous because one's motivation is hardly pure. It
is said that when one practices Vajrayana, it is like a snake
climbing inside a bamboo pole. It needs to continually climbing
upwards, if not it could easily slide down. If one wants to learn
Vajrayana, one needs to find an excellent teacher, who is qualified
to teach you. And in the scriptures, it is advised that the student
takes 3 years to examine the teacher. The teacher must have
compassion, and hopefully has at least a glimpse of
emptiness.
Mahayana is sometimes also referred to as the Causal Path, while
Vajrayana the Result Path. This is because Mahayana practice
basically gets one to plant the seeds of Bodhisattvahood and
Buddhahood. Whereas Vajrayana practices operate from the premise
that your original state is already enlightened (Buddha Nature, or
basic goodness), therefore all you need to do is to remove the
temporal contaminations (greed, anger, ignorance, pride, jealousy
etc) and get used to your Buddha Nature. (Pardon me if it's not
very clear, I'm just trying to grossly summarize the Vajrayana
practice here.) Today, Vajrayana is practiced in Tibet, Nepal,
India, China, Japan, Singapore, Malaysia, I heard in Myanmar there
is too, but I'm not too sure.
It actually doesn't really matter which vehicle one chooses, as all
will eventually lead to liberation. It also depends on our own
karmic connections with the various traditions.
If you are interested to find out more about Tibetan Buddhism, you
could contact the following centres:
Sakya Tradition: Sakya Tenphel Ling
http://www.sakyatenphelling.org/
Kagyu Tradition: Karma Choying Kunkyab Ling
http://www.karmachoying.org/
(the Karma Choying centre often invites very good teachers. check
out the website for updates on upcoming events)
Nyingma Tradition: http://www.palyulsg.org/
Gelugpa Tradition: http://web.singnet.com.sg/~chungsa/
