Got this, thought nice to share:
"Why do Buddhists bow" an interested person asked Lama Surya Das. "What is the purpose? I often see them bowing, and hear about large numbers of bows beings practiced in Buddhist meditation halls and temples".
Lama Surya Das: "Yes, there is a lot of bowing going down. Bowing is a common practice in the Orient, both within and outside of religious circles. Bowing is a way we express respect and reverence as well as a form of greeting. In India, for example, people bow and say "Namastay" while doing so, which means "I bow to honor the divine in you" and signifies a word of greeting and meeting that remembers and recognizes the spirit, like the Hebrew word shalom, and is used for both coming together and parting; these words are extremely rich is spiritual redolence.
In Tibet we bow and say Tashi—deleks, meaning "excellent luck and auspicious good fortune to you." Disciples and devotees bow to their gods, holy icons ("murtis" images), and Hindu gurus in India, kneeling or prostrating on the floor, often at their guru's feet; this is called "pranam".
In Japan, China, and the entire Far East bows are used when coming together and parting, instead of handshakes or kisses on the cheek. As Catholics genuflect upon entering a cathedral. Bows are commonly offered when entering or leaving a temple, shrine, pilgrimage place or spiritual circle of any kind. Zen Buddhists use a short form of the kneeling bow, simply placing their palms together at their heart chakra and bowing to another; this is called "gassho" in Japanese. My zen master in Kyoto explained that bringing the two hands together at the heart represents the reunion of all polarities and duality in our spiritual center, the heart of enlightenment.
The seventh century Indian Buddhist master Shantideva, the Gentle Angel, author of the Mahayana classic "Entering the Path of Enlightenment", said that just to raise one hand in a gesture of respect and reverence sows the seed of enlightenment. Since that time, bowing has become am intensive spiritual exercise. The devout get down on their hands and knees and then lower themselves face down and flat on the floor; this is a full bow, called a prostration. This gesture symbolizes yielding, surrender, reverence, and taking refuge in that which is good, true and holy. In fact, this outer form of reverence simply reflects an inner gesture of awareness, and is not very meaningful unless done in such a spirit.
Prostrations such as these are an important part of the most common foundational practices of Tibetan Buddhism (or Vajrayana), called "ngondro"(literally, "preliminary practices"). Over the course of several months or longer, the beginning practitioner is expected to complete at least 111,000 of these full-body prostrations along with chanted Refuge Prayers as part of the ngondro practices (which include several hundred thousand others prayers, purification mantras, offerings, mandala, and devotional meditations). This is considered an excellent body-speech-mind-involving practice and a purification of karma accumulated through those three doors, and thus provides a firm foundation for deeper Vajrayana meditation and yoga; it is also something we continue to practice in small numbers on a daily basis throughout our lives. I remember my aged Dzogchen master, the late great Dudjom Rinpoche doing this on a daily basis, even into his eighties. My own late Tibetan master Kalu Rinpoche explained that prostrating our five limbs on the ground reintegrates our separate sense of being into oneness with the pure original sacred nature of the five natural elements—earth, water, fire, air and space, each of which is like a goddess that our godly nature embraces in the oneness of mystical tantric consummation.
The truth is: completing these 100,000 prostrations, know as "chak-boom" in Tibetan, was one of the hardest things I've ever done in my life. My teachers had me complete ngondro thrice during the Seventies and Eighties in order to fully receive and practice three different Vajrayana lineages. If that sounds like a lot, the fourteenth Tibetan saint Tsongkhapa is known to have performed over a million prostrations during his four year meditation retreat in a cave, while an aged lama's wife I know in Sikkhim has completed the ngondro practices sixteen times!
Zen practitioners likewise offer large numbers of full prostrations to the Three Jewels in the Buddha Hall of their meditation centers and monasteries. My teacher used to offer 108 each morning before the large Buddha statue on the altar of his temple, even at an advanced age. Three-fold bows are also offered when entering the presence of spiritual masters and teachers, taking advantage of the presence of an exalted embodiment of the principle of enlightenment — in the form of a living master — to reverence that immanent principle; in other words, bowing to the Buddha-nature and the Buddha as embodied by a venerable spiritual teacher. For as Buddha suggested, reverence the teaching even more than the teacher; cherish the spirit of the Dharma/law more than the letter of the law; value practice more than theory, and experience more than beliefs.
Many of us have seen the saintly Dalai Lama — in pictures or on TV, if not in person — putting his palms together before his face or at his chest and bowing to whomever he meets, whether person to person or before a large audience. He is bowing to the Buddha within each being, and inviting entrance therein. This is a way of practicing that belief on a regular basis, of training oneself in the highest, deepest mystical principles through a simple daily exercise which can make every single encounter deeply meaningful.
Such a bow is not an empty gesture. Bowing is a yoga-like practice with many different levels of meaning. Bowing is a way of being, a way of giving, of offering up and opening oneself. My teachers taught me to drop whatever I was holding onto, put my hands together at my heart, and bow to all beings seen and unseen, thus cherishing and respecting all forms of life. This is a practice of what Mahatma Gandhi called "ahimsa", which means truth in nonviolence. Bowing makes us vulnerable, humble, simplifies things and helps us arrive more fully and be centered upon the present moment and more fully enter into and inhabit the holy now. Whom then can we harm?
When we drop what we have been holding onto, which is required in order to put our palms together and bow; we free ourselves of past and future encumbrances, and our hands are more ready either to help or simply to be at rest. A lot of excess baggage falls away, which is a real relief. We get a chance to enjoy inner peace, at least for that moment.
I myself feel that, when we bow, we lower our guard and surrender to our innate spiritual nature, our Buddha nature. Placing ourselves closer to the earth, as we do when we bow—or when we garden, for that matter, which is like a natural meditation—we get closer to our own ground of being. We lower ourselves before the infinite mystery, the ungraspable, unknowable existential mystery of the universe, and open ourselves to reality beyond our conceptual limitations.
I have a Tibetan lama friend who had polio as a child in a refugee camp in India. Because he can't kneel down, he simply puts his hands to his chest, palms together, and bows in his mind. He assures me that there is nothing missing in such practice.
I didn't always enjoy bowing as much as I do now. When I first lived in the Himalayas in the early Seventies, the idea of prostrating before someone or before a graven image was anathema to me. I guess I had a lot of Judeo-Christian background and conditioning. "I won't lower myself to anyone!" I thought. Eventually I learned to enjoy bowing, and discovered how profound and beautiful bowing practice is and can be.
Now I see bowing as an elegant traffic signal of the body, voice and mind. Every bow says: Slow down. Quiet. Drop the ego. Yield. Meditation zone ahead; proceed with caution. Bowing is a mindfulness practice. When we offer a complete bow, or even just respectfully incline our hearts and minds as entering a sacred space or making contact with another being; bowing is a way of removing our mental and emotional armor, along with other ego baggage we may be burdened with. It is like leaving our shoes and luggage at the door of a shrine.
In Buddhism itself, scriptures tell us that Buddha realized his great awakening (enlightenment) while sitting beneath a tree in the wilderness of Northern India at Bodh Gaya. It is told that at that auspicious moment 2500 years ago, which occurred just as the morning star rose over the eastern horizon; as Buddha awoke, the entire natural world bowed to him in gladness, recognition and veneration. Buddhist sutras say that the earth trembled and trees, flowers, and tall blades of elephant grass bent down in respect. We join in reverence and enter into that moment each time we bow.
The best essentialized bowing practice I know and find eminently doable every day is to simply raise joined palms before the heart and lower one's head in a gesture of surrender and letting go. This silent bow is my favorite form of contemplative, wordless prayer."