5 ideas
Studying the Buddha way means studying the self; studying the self means forgetting the self; forgetting the self means being actualized by the myriad things. When the self is forgotten, the boundary between self and others falls away, and no trace of that realization is left behind to cling to.
A person in a boat who watches the shore may think the shore is moving, but if they look at the boat they see that the boat is what moves. In the same way, when you look at the world from a confused view of body and mind, you mistake your own changing self for something fixed.
Firewood becomes ash, but you should not see ash as after and firewood as before. Each dwells in its own dharma position, with its own before and after, yet each is cut off from them. Life and death work the same way: life does not become death, and each is a complete, whole moment rather than a stage in a sequence.
Enlightenment is like the moon reflected in water: the moon does not get wet and the water is not broken. The whole moon and the entire sky can be reflected in a single dewdrop in the grass. The vastness of realization does not obstruct the individual person, just as the dewdrop does not obstruct the moon.
A monk asks Zen master Baoche why he uses a fan when the nature of wind is permanent and reaches everywhere. Baoche replies that the monk knows the wind is permanent but not that it reaches everywhere, and then simply keeps fanning. The point is that an inherent Buddha nature does not make practice unnecessary: realization is made actual only through continuous practice.