The idea is just that everyone gets to own or lease or whatever you want to call it some land and does not have to buy it from others who have accumulated it over the generations and keept it for themselves. If you want more land than your share, you can get it from someone who doesn't want their entire share, but only until their death when they lose control over that land and therefore can also no longer lease it to you. At which point you have to return it or find someone else who will lease the same amount of land to you.
I guess you could say that my idea is that you get control over a certain area of land during your lifetime but it does not have to be a specific piece of land and you can freely exchange and transfer this control as you like, but not past your lifetime.