Silence is the most potent form of work.

The guru is quiet and peace prevails in all. His silence is more vast and more emphatic than the scriptures put together. In fact the guru is always within you.
The guru's silence is the loudest teaching.
It is also grace in its highest form.

Silence is the true teaching.
It is the perfect teaching.

It is suited only for the most advanced seeker.

The others are unable to draw full inspiration from it. Therefore they require words to explain the truth. But truth is beyond words. It does not admit of explanations. All that is possible to do is to indicate it.