I’ve mentioned and quoted Eugene Peterson’s talks on the Beatitudes a number of times already. (They can be purchaced online in mp3 format at Regent Bookstore).
Early on in the series Peterson does a beautiful introduction to the Beatitudes – which he later expands upon. I’m taking them out of there context here, but there’s still much to be gained by reading them. Here’s the summary (note how these  tally up with Jesus’ words recorded in Matthew 5):

Instead of grasping, we let go – & God GIVES
Instead of trying to run things, we accept our incompetence, relax with our inadiquacy – & God EMPOWERS
Instead of indulging or denying out appetites and desires we let them act as guides that lead us to God – & God FULFILLS
Instead of getting angry and frustrated and set out to set things right for ourselves, we get on with forgiving those who are messing up the world – & God RESTORES
Instead of trying to find some knowledge or teaching or accomplice to get what we want, we purge ourselves and simplify ourselves – & God REVEALS
Instead of looking on others as competitors we decide to treat them as companions – & God BEFRIENDS
Instead of trying to create utopian conditions out of our own good intentions, placating the opposition, we accept the reality that our life in the Kingdom provokes some people to their worst behaviour – & God SUFFERS

Peterson goes on to say:

Each Beatitude deals with not doing. The images of wells is helpful, because a well is emptiness – which makes possible a fullness…
After listening to Jesus, we say, ‘I’m going to go out and see what God is doing and how he does it and see if I can get in on it – and try not to get in the way too much.’

He goes on to say, it is God who does the work of ‘creation’ and ‘salvation’. He is the one doing the creating and saving, and he graciously allows us in – but we need to watch and learn as we are just participants. (Peterson tells a great story which helped me understand this, you can listen to it here – the story starts about 44 minutes into the talk)
Note: The use of ‘salvation’ needs to be understood in context. Matthew places Jesus on a mountain with this speach – clearly making reference to Moses on Sinai and the Ten Commandments.
At Sinai, the work of salvation has been done, the Isrealites have been granted freedom from Egypt, and now through Moses, God states how things are. The Ten Commandments were not there for the Isrealites to earn their salvation – but to show them how to live in their freedom which God granted to them by his grace.
Grace is not just a matter of release from captivity or extravagant forgiveness, clearly it is this, but grace is multi-dimension-ed. We experience grace by living in it. So the forgiver experiences grace just as much as the one who has been forgiven, and the one who gives a cup of water is living in grace as much as the one who recieves, Jesus even states, that ‘it is more blessed to give than to recieve’.
As with the Ten Commandments, so it is with the Beatitudes: this is what life looks like in the freedom and grace of God. Perahps, another way of saying it perhaps is – these describe reality.

“Are you tired? Worn out? Burned out on religion? Come to me. Get away with me and you’ll recover your life. I’ll show you how to take a real rest. Walk with me and work with me—watch how I do it. Learn the unforced rhythms of grace. I won’t lay anything heavy or ill-fitting on you. Keep company with me and you’ll learn to live freely and lightly.” Matthew 11:28 (The Message)