"From this moment onwards
Source: Lamp for the Path
When we honor the Bodhisattva Vow in our hearts and in our minds with a strong commitment, we are making a determined effort for all of eternity to be of service and help to life.
There are ceremonies for taking the Vow, but it is not the ceremonies that matter so much as the commitment to Love and Understanding.
I think any open minded person of any religion or non-religion can take the Bodhisattva's Vow of serving others as they work toward an enlightened being.
The Bodhisattva, to me, is a state of being and not a concept that is owned by any particular religion or sect. Rather, What makes someone a Bodhisattva is her or his dedication to the ultimate welfare of other beings, as expressed in the prayer: 'May I attain Buddhahood for the benefit of all sentient beings'."
To the Occidental mind, this present life is really all there is. There may be a judgment and then an eternal heaven or damnation or there may be nothing after death, depending on whether that mind has a scientific or religious bent. But from an oriental perspective, this is only one of many lives.
If we allow ourselves to consider that consciousness cannot be cut into pieces, burned, buried, or destroyed but is in the very fabric of everything; then we can come to a greater understanding of what this present life is. Life is an experience of consciousness and it is no way a product of our own self or of our own species. Life is a constantly changing and evolving experience. Consciousness is the basis of life and it doesn't die when this particular life ends.
If we consider this broader perspective and understanding of life then we see how the Boddhisattva Vow is not only beautiful and inspiring, but it is liberating.
Sure a life of Service and Love may seem limiting to the close-hearted and the close-minded, but it is a life that offers us freedom from the greatest of prisons--our self. Taking the Bodhisattva's Vow makes us break the chains of the self and opens us to the true reality of our existence. That reality is nothing more than there is no separate self, but that we are all a part of each other.
In truth, when we honor and love others we are honoring and loving the life that we all possess. Working to serve others is liberating because it moves us past an illusory idea of what brings joy and happiness.
Sure the Bodhisattva's life of service is demanding and often difficult. But life itself is demanding and difficult. There will always be sorrow and troubles in life, but the Bodhisattva doesn't take those sorrows and troubles personal. Rather, he or she knows that this is the universal condition of life. This understanding of the truth of life allows the Bodhisattva to move beyond the limited outlook of Selfism and into the expansive truth that we are all of each other.
I have little doubt that there have been innumerable Buddhas and Enlightened Beings in the eons of time. They have at some point traveled the very same levels of consciousness we possess right now. Taking the The Bodhisattva's Vow is nothing more than traveling the path of Buddhahood (Awakened and Enlightened Being), whatever your religion or lack of religion. The Bodhisattva's Vow will not only, clearly, help other living beings cope with their sufferings and traumas but it also liberates those that take it from the tremendous suffering and trauma of a limited self focus.