All the Buddha qualities such as fully developed love, compassion, wisdom and so on, already exist in our own hearts and minds. All that is needed is to bring them out and to express them fully. However, it doesn’t seem to work very well to say something like, “Oh yes, I will just meditate on compassion and bring out Great Compassion”. You have to have a method to bring out qualities like compassion, joy, faith and so on, and because form is what we are used to, because it surrounds us all the time, it is usually necessary to work with some kind of form. So you practise with a form that has an orientation toward the quality you are trying to bring out, and maybe after doing that for a very long time you have a momentary experience of the quality. Then for the first time you know that quality as a direct experience, even if only as a momentary glimpse.
You have to be careful not to be seduced by the form; in other words, although the formless experience which comes out of form is real and genuine, you carry an underlying belief that the form itself is necessary as a solid basis for it. You think, “I have put a lot of hard work into this. I have got a recognisable, solid experience out of it, and that experience is growing. The best thing to do is to put in more effort”. However, at some point the trick is to put in less effort; to let go of the form aspect and try to rest in the formless experience of compassion or whatever quality it might be.
If you let go of the form too soon, the form dies and so does your experience. If you let go of the form too late, you become too sucked into the form (you have put all your money on it as it were) and you can’t give up your investment in it, it is too great. It is a bit like jumping from one galloping horse to another. If you jump too early you will fall to the ground in the gap between the two horses. If you try to delay your jump the horse you are riding will get too exhausted to keep up with the fresh horse. It is also like a relay race, passing the baton from one person to another; it has to be done in the right way and at the right time. If you let go of the kyerim in the right way you can accomplish the dzogrim very quickly. There is a relevant Tibetan story of a man getting onto a horse; the man accomplishes the kyerim as his left foot enters the left stirrup, and then accomplishes the dzogrim as his right foot enters the other stirrup. It can happen very quickly like that, but for most of us it is a gradual process.
When you do let go of the form and rest in the compassion or joy or faith in itself, the experience is tremendously increased. This is really the point of the kyerim and dzogrim principle in fact. All the practices of form have a formless aspect into which they lead, which is vaster, more real and powerful than the form itself. This principle works at all levels, all the way from Hinayana where you are trying to develop dhyana and samadhi, right up to Ati where, even though they don’t use the terms kyerim and dzogrim very much, the principle is still there.