All beings without number I vow to liberate.
Endless blind passions I vow to uproot.
Dharma gates beyond measure I vow to penetrate.
The great way of Buddha I vow to attain.
- As translated by Roshi Philip Kaplan.
When they are recited with conviction, chanted, they are empowering and moving as part of your meditation practice.
The first vow is not to be taken literally. The bodhisattva could not liberate all beings. But what he or she can do is dedicate his practice and his merit to the enlightenment of all others, and pray that his efforts be a drop on the ocean of activity of all other bodhisattvas who work to liberate and bring enlightenment to all.
The second vow is self-explanatory. We all have endless blind passions that are the product of our mind and our life experience. Until we uproot those passions by turning our will and our life over to the care of our true Buddha nature, surrendering our ego to its care, there is no peace, there is no happiness.
And so this vow is inward-directed. The bodhisattva knows that he cannot uproot someone else's passions; only the person himself can uproot those passions. And the bodhisattva knows that while he may no longer act on those blind passions, and he does not feed them, they are still within him; they will always be a part of him.
Re the third vow, what does it mean to penetrate dharma gates? Dharma has two meanings. The first is "reality." Tradition says that there are 1008 gates to reality. Symbolically the gates are without number. We are raised not to experience reality as it is but instead reality as it is seen by our mind. And so there is no end to the dharma gates to be penetrated. And it is one of the great vows because if we do not see reality as it is, free of the mind, there is no end to samsara, there is no nirvana.
But dharma has a second meaning, and that is the teachings of the Buddha. They also have untold gates or barriers presented by our mind. The Buddha dharma is at such a variance from the way we have been raised and taught, the way we have learned to relate to ourselves and the world around us, that was can only penetrate the teachings by going beyond our mind to our spirit, our true Buddha nature, our heart. By freeing ourselves from the control of our mind and being one with our true Buddha nature, we are able to experience the truths of the Buddha dharma from within ourselves, and so enable us to see reality as it is.
The final vow is to walk the path of the Buddha, to walk the Noble Eightfold Path (see my post of that title). To attain this vow means once again freeing oneself from the control of one's mind, turning your will and your life over to the care of your true Buddha self, surrendering your ego to its care. For without being free of the mind, one cannot engage in Right anything.
Indeed, the prerequisite, the condition that must be present to implement the Four Vows, which is to be a bodhisattva, is to have turned you will and your life over to the care of your true Buddha self, surrendering your ego to its care.
This does not mean that you cannot begin walking the paths set forth in the vows until one is completely free of the control of one's mind. But it does mean that one has to be on that trajectory. For more on freeing yourself from the control of your mind, see my post, 'How to Free Yourself . . ."