Everyone on the face of the earth is represented as soil by this farming story found in Mark 4:3-20. Isn't it interesting that Genesis 2:7 says, "God created man from the dust of the ground." Jesus scatters His good WORD all over earth and it is received either by hard, rocky, thorny, or good soil.  

Jesus is the sower and we, by extension, have been given a mandate of sharing the gospel seed. It is important in physical and spiritual agriculture to understand what soil is like in order that we may be effective at sowing.