The Land of Inhabitation
There are four soils the Lord spoke about; there are also four different lands Israel were in.
There is one soil which is good soil and fruitful: this represents the land of promise.
The other three soils were unfruitful, same with the three lands Israel were in throughout history.
The wilderness represents the seed that was scorched and had no root. The thorns would be the land of Exile which were choked out.
I would consider Bondage and Slavery, the rocky soil, which the birds ate, since oppression comes from the evil one.