The following quote is taken from 'The Pocket Thich Nhat Hanh' (click)
published by Shambhala Pocket Classics.
" My dear friends, suppose someone is holding a pebble and throws it in the air
and the pebble begins to fall down into a river.
After the pebble touches the surface of the water, it allows itself to sink slowly into the river.
It will reach the bed of the river without any effort.
Once the pebble is at the bottom of the river, it continues to rest.
It allows the water to pass by.
I think the pebble reaches the bed of the river by the shortest path
because it allows itself to fall without making any effort.
During our sitting meditation we can allow ourselves to rest like a pebble.
We can allow ourselves to sink naturally without effort to the position of sitting,
the position of resting.
Resting is a very important practice,
we have to learn the art of resting."