Ajahn Brahm has used the metaphor of sand on a beach to describe consciousness. At a distance when you look at a beach it looks like it is a solid surface but up close when you look at each grain of sand individually you see that there are gaps between the sand. In a similar way, our ordinary experience of consciousness is that it is an ongoing process with no gaps or spaces, but when the mind is clear (after deep meditation) we can see that there are instances/moments of consciousness that arise and pass away, with gaps in between.
Consciousness is said to be like sands on a beach, it is like a stream, but these are just metaphors to help us understand such a subtle process.
Four types of letting go:
1) Giving; expecting nothing back in return
2) Throwing things away
3) Contentment; wanting to be here, not wanting to be anywhere else
4) "Teflon Mind"; having a mind which doesn't accumulate things
- Ajahn Brahm