We say, "railway track," but actually there is no such thing. Sincerity itself is the railway track. The sights we see from the train will change, but we are always running on the same track. And there is no beginning or end to the track: beginningless and endless track. There is no starting point, no goal, nothing to attain. Just to run on the track is our way. This is the nature of our Zen practice.
You should get rid of excessive things. If your practice is good, without being aware if it you will become proud of your practice. That pride is extra. What you do is good, but something more is added to it.
To be natural is something we must work on.
naturalness is, I think, some feeling of being independent from everything, or some activity which is based on nothingness. Something which comes out of nothingness is naturalness, like a seed or plant coming out of the ground. The seed has no idea of being some particular plant, but it has its own form and is in pefect harmony with the ground, with its surroundings. As it grows, win the course of time it expresses its nature.
Everything is Buddha's activity. So whatever you do, or even if you keep from doing something, Buddha is in that activity. Because people have no such understanding of Buddha, they think what they do is the most important thing, without knowing who it is that is actually doing it. People think they are doing various things, but actually Buddha is doing everything. Each one of us has his own name, but those names are the many names of one Buddha. Each one of us has many activities, but those activities are all Buddha's activities. Without knowing this, people put emphasis on some activity. When they put emphasis on zazen, it is not true zazen.