The meditation on the Dharmakaya is the making still the waters of the ocean of our root mind of great bliss. Every object is like a wave on the ocean arising from karma and delusion. Delusion activiates contaminated seeds which create waves which reflect the appearance of contaminated objects. As I make still my mind, the waves pacify, the contaminated appearances cease, the mind becomes increasingly clear until it is clear light.
When you allow the waves of contaminated appearance to subside, you are able to abide directly with your guru and you realize that he is literally behind and the real nature of everything.
The most important possession of anybody is their mind. It controls everything and enables them to do anything. Yet, this is the possession we completely neglect, to our peril. We must care for our mind, keep it clean, powerful and well functioning so it can take us to where we want to go. We need to care for our mind like a car enthusiast would, like those guys who wash their car and care for every detail obsessively. Right now, my mind is dark, dirty and uncontrolled. I need to give it light, clean it up and get it in good working order. If I do everything but this, which is what I and others typically do, then I won’t be able to do anything. But if I do do this, I will be able to accomplish anything. Our mind is like a wild horse that we have no choice but to ride. We must bring it under control and become the one in charge.
The above discussion is correct, but not fully correct. It grasps at us as having two different minds in us. In reality, we have one mind. It is the same mind. But it is currently completely out of control and we are identifying with and following one of the illusions being kicked up by the fact that our mind is uncontrolled, contaminated and distorted. We grasp at ourselves as being an illusory wave. We need to see past this illusion, realize it is not who we really are, and instead stay focused upon the pure ocean. We bring the ocean of our mind under control, allow it to become still. As we do so, the illusory contaminated reflections which we remain imprisoned within (samsara) will subside and we will be left with the purity and clarity of the Dharmkaya. The conventional guru is a focal point of purity within our mind that we can more easily identify and identify with. By drawing closer to it and coming under its influence we come to center ourselves within a point of calm. Within the space or perspective of the guru, everything is harmonious and symmetric. Everything is clear. We know what to abandon and what to attain, we know what is deceptive and what is reliable. By acting from and abiding within this space, we are able to very quickly pacify the uncontrolled waters of our mind. Once sufficiently pacified, we eventually leave this conventional guru behind and pacify and dissolve even it and come to abide in the complete tranquility, purity and stillness within.
When dissolving everything into the DK, it is important that it not be something abstract. You are not meditating on the abstract idea of all phenomena dissolving into B&E, but rather on the first hand, living experience of this happening right where you are with the appearances around you. It should feel as your first hand experience with respect to the actual world around you. Then, likewise, when you generate the pure world, you should also experience these appearances as your first hand, living reality.