Well there are formal vows you can take, that you are going to follow the bodhisattva path. But that’s not really what makes you a bodhisattva. More exactly it makes you an “aspiring bodhisattva” who is trying to follow the bodhisattva path and has the aspiration to become a bodhisattva and is going to keep trying and pick yourself up when you fall.
Many Mahayana Buddhists have taken those vows and so are aspiring bodhisattvas. The vows though are interpreted in a soft way - you have to be kind to yourself, they aren’t ideals, as you could never measure up to them. They aren’t things you have to force yourself to do or they’d be impossible. They are aspirations.
Meanwhile a Therevadhan Buddhist might not have taken those vows at all, and yet be linking to true compassion and loving kindness in a genuine way in their practice.
To truly be a bodhisattva, the main thing is putting others before yourself. I don’t think that the conceptual overlay of thinking in terms of buddhahood, enlightenment, etc really is that important. If it was you could only be a bodhisattva if you were a Buddhist, but for instance the past stories of the previous lives of the Buddha talk about him being a bodhisattva as an animal.
Also Buddhists often talk about non Buddhists as showing the compassion of a bodhisattva.
So, I think it’s really just this matter of others first. And it’s not something you can prove to anyone else, if you are doing it to try to prove that you are a bodhisattva then chances are that actually you are putting yourself first :).
It’s also rather simple. The bodhisattva path as described in Buddhist texts often seems totally impossible, it’s like an ideal that you could never imagine ever reaching. Especially also when they talk about bodhisattvas having remarkable powers too. But being able to do things that are close to miraculous is not what bodhicitta is about. Rather it is a miracle, yes, but an ordinary miracle, that anyone can link to, but few do, of turning around, and putting others before themselves.
Mothers often do this with their children. And most people will if they are in a situation that somehow touches them. With a bodhisattva though, it’s like that with all beings, no matter how awful they are, or ugly, or disgusting - you aren’t judging them to see if they are good enough, or closely related enough to you, or cute enough, to be recipients of your compassion :). That’s the main difference really.
Also it’s not about helping large numbers of people. You don’t have to go to Africa or Syria or some trouble spot to try to help the people there. Of course some who do will be bodhisattvas, but you don’t have to do dramatic things like that. Just in ordinary situations. Could be a nurse, could be a teacher, a pop singer, someone in a band, an artist, a gardener, just doing their thing, but they have this turned around, putting others first. In ways that may be totally invisible to others too. They could be harsh, abrasive, difficult characters sometimes, that you want to help others doesn’t necessarily mean that you make things easy for them!
So, it’s my understanding that there may be many bodhisattvas, and I may meet them every day, and I wouldn’t know about it.
So when you ask “How does one become a bodhisattva”, that seems like a wish to become a bodhisattva and if so that’s a very positive thing to wish for.
So, there isn’t really anything you can do to become a bodhisattva instantly on the spot. You can’t take a vow and instantly on the spot you are a bodhisattva. But you can aspire to it, and you can take the bodhisattva vow as part of that aspiration, which of course is an aspiration for all beings not just for yourself. And some may be bodhisattvas already.
In Tibetan Buddhism at least they teach that there are three main styles of bodhisattava, the “King bodhisattva” who wants to help all beings, but decides that the only way they can do that is to work on themselves first, they are acutely aware of how their mistakes hurt others and feel they have to work on themselves first before they can help, then the “Ferryman bodhisattva” who help themselves and others together, and the “Shepherd bodhisattva” who gives no thought to themselves at all and is just doing what they can to help others with all their flaws, as is. This is not really something they can choose between, and is rather part of the situation they find themselves in. It’s not that one is “higher” than the others it’s just the way it is.
You can’t really tell which they are by their behaviour either - a bodhisattva could do a long meditation retreat for instance to work on themselves as a king bodhisattva, or it could be something they feel is helping themselves and all others together, or it could be that they have no thought for themselves at all and are doing the retreat because they feel this is what they can best do to help others at that moment in time. That’s an idea we don’t really have so much in the West, that by meditating, you aren’t really separating yourself away from the world, but are part of it, in a way as you meditate it’s like all beings and the non material world too are joining in that meditation. So a bodhisattva can meditate only for the benefit of others if they are doing it as a shepherd bodhisattva.
There are meditations you can do to help to open out to others and develop loving kindness and compassion. The wish to become a bodhisattva by itself is seen as something very positive. Indeed Tibetan Buddhists often make the prayer: “may the precious bodhicitta be born where it has not yet taken birth, where it has been born may it not fade but grow and grow.” It’s common to make that prayer at the end of every meditation as s dedication.
There “bodhicitta” means the wish to help all beings.
JANGCHUB SEMNI RINPOCHE
MACHEY PA NAM CHEYJUR CHIG
CHEYPA NYAMPA MAY PA DANG
GONGNAY GONGDU PELWA SHOG
= dedication prayer often made at the end of a meditation in Tibetan traditions: ““may the precious bodhicitta be born where it has not yet taken birth, where it has been born may it not fade but grow and grow.”
Mani Wall in Zanskar The text is Tibetan for Om Mani Padme Hung which you can translate as “Hail to the jewel in the lotus” which is a mantra for compassion and bodhicitta.