Tucked into a few verses in our parasha are the laws of dividing up Eretz Yisroel to the various shvatim. There seemed to have been three different methods employed.
First of all, it says that they prorated the different parts of Eretz Yisroel so that the apportioned areas were all of equal value. They did not divide up based on square footage, but, as Rashi says, they divided it up based on value and ability to use the land productively. We would therefore describe this as human effort that divided up and apportioned Eretz Yisroel.
Secondly, Rashi also says that Elazar the Cohen would be dressed with the urim v'tumim, and he would proclaim with the Divine spirit upon him: "if the following tribe comes up in the lottery, then this will be the land he gets". In other words, it was heavenly ordained.
But the primary mechanism for dividing the land to the tribes is, as is written in the parsha, through a lottery. Rashi adds that when the lottery was finally drawn, it would proclaim, "I, this land, belong to the following tribe".
The different types of methods used to divide the land could be categorized as: a) human effort and a rational apportioning, referring to the evaluating the different portions of Israel and seeing what is similar in terms of value, b) a Divine commandment by the means of the urim v'tumim, where the cohen told us what each tribe is supposed to get, and c) the lottery, which in the parsha seems actually to be the most important of the three. This is strange, because a lottery seems to imply neither a human thought process nor a clear directive of G-d. What is the point of the lottery? Why is it the core method used for dividing up the land of Israel?
The settling of the land of Israel represents a new phase in the development of the Jewish nation. During their sojourn in the desert, they really were living in a Divine bubble. Nothing of the physical world really meant much to them. They were in an uninhabitable desert, with no natural means of survival. Their primary staples were all miraculous - the water from the well that travelled with them, the mon that served as their food, and the Divine clouds that served as shelter. This was a mode of life that represented the purely spiritual. In Eretz Yisroel, however, they would have to connect to the land and be able to express their spirituality through the physical world. The division of the land into different types of terrain meant that they would begin to notice specific talents that each one had which were relevant to the physical world. The different personalities of a person who is a farmer, a merchant, or a soldier all emerged in the Land of Israel; in the desert no one had to farm, no one had to do business, and only very few times did they have to fight. In Eretz Yisroel however, each group hard to find its role and fulfill it successfully.
This is the deeper understanding of the division of Eretz Yisroel. The land has many different attributes - there are lakes and rivers, deserts, fertile land, and land that borders on enemy territory. The land that each tribe was given was the land that was most uniquely suited to their talents and hence their mission.
When we each ask ourselves, "what is my personal mission?", the best guide to disvoering the answer is taking stock of our resources and talents and the needs of the world around us. The Gr"a (Mishlei 16:4) states that it was the task of a prophet to instruct people as to what their mission in life was. When we don't have a prophet to tell us what our mission life is, we need to take a look at our personal resources and extrapolate as what must be our mission. For instance, a person who has musical talent obviously has a mission in line with that talent. It may or may not be readily evident what it is, but the fact that these are his resources tells him that this must be his mission.
The lottery is a complex device. On the one hand, it is not a rational human endeavor as was the conscious dividing up the land. On the other hand, it wasn't an open commandment of God; after all, it simply was the drawing of a card. But the the lottery "expresses itself", in that each lot that came up in the lottery proclaimed that "such and such a tribe is designated for me". In other words, the piece of land, the resource itself, indicated which tribe should get it.
The lottery was therefore the procedure that most clearly expressed the essence of Eretz Yisroel. The lottery is not physical cause and effect, nor is it a clear Divine statement. Rather, it starts as a physical fact; one piece of paper came out and then another piece of paper matched up with it, and that's "merely" chance. But then the lottery itself proclaims that, "I belong to a certain tribe", it means that this is what Hashem had in mind for it all along. Eretz Yisroel is the place with this type of Divine Providence, where the physical realities are expressing Hashem's will. Eretz Yisroel is the place where each tribe finds its physical and spiritual niche. It's the place where each tribe is given the resources it needs to fulfill its unique mission.
Even today, when we do not have the old divisions of Eretz Yisroel, and we don't know - as far as the majority of us are concerned - from which tribe we descend, we still can examine the resources Hashem has given us and extrapolate from there what must be the mission that HKB"H intended for each of us.