In the Parable of the Sower, Jesus compares spreading the word about the Kingdom of God to scattering seeds.  The kingdom, like any seed, will take root only when it lands on good soil.
Here’s the parable without Jesus’ explanation:
A sower went out to sow. And as he sowed, some seeds fell along the path, and the birds came and devoured them. Other seeds fell on rocky ground, where they did not have much soil, and immediately they sprang up, since they had no depth of soil, but when the sun rose they were scorched. And since they had no root, they withered away. Other seeds fell among thorns, and the thorns grew up and choked them. Other seeds fell on good soil and produced grain, some a hundredfold, some sixty, some thirty. (Matt. 13:3-8; see 13:18-23 for Jesus’ explanation)
Gardeners talk about soil.  Good soil contains nutrients, the right pH level, and the kind of texture that allows plants to take root.  Poor soil lacks at least one or maybe all of these qualities.
Good soil gives us fruit and vegetables and flowers.  Experienced gardeners know how to amend even poor soil so that it too will promote plant growth.
For us non-gardeners, soil is just a synonym for dirt.  Not for a gardener!  Soil is for growing.  Dirt is just what you get on your clothes or your kids track through the house.  
In other words, dirt is a mess.  Don’t bother planting in it.  Just clean it up.  At least, that’s how we look at it.  God apparently sees things differently.  Lucky for us!

Consider how God got started with us in the first place: “The LORD God formed the man of dust from the ground and breathed into his nostrils the breath of life.” (Genesis 2:7)  God took what you and I might count as dirt and breathed life into it.  And there was Adam: Dirt Man.  That’s basically what the Hebrew for “Adam” means: Dirt Man.
That’s not to say that Adam was just animated dirt.  He’s more than that.  We’re more than that.  God breathes his Spirit into the dirt and it becomes something entirely new: Kingdom Soil.
God takes whatever anybody else might consider a hopeless mess and makes it into kingdom soil.  Just the right place for God’s good purposes to flourish and his redeeming love to grow.  Lucky for us!
Life is messy.  We say things and do things—and we neglect to say and do things—every day.  Sometimes it doesn’t really amount to much.  Sometimes it looks remarkably like a train wreck, maybe one unfolding in slow motion.
If we think our marriages and our kids and our conduct and our character have to be perfect in order for God to do anything with us—if we have to make ourselves good soil for the kingdom to take root—we’re in deep trouble.
It is true.  The kingdom needs good soil to flourish.  But God is very aware that we have a soil problem.  Let’s turn to Genesis again.  This time, God is speaking to Adam and Eve after they have eaten the fruit of the Tree of the Knowledge of Good and Evil.
God says to Adam, “Cursed is the ground because of you.”  (Genesis 3:17)  In other words, you’ve fouled your soil.   You’ll be contending with rocks and thistles your whole life.  What a crummy place to grow the Kingdom of God!
However, God does not walk away and wish them, wish us, the best.  He knows that we cannot amend the soil of our lives.  That takes a Master Gardener.  And as it turns out, that’s what he gives us.
In John’s account of the resurrection, Mary Magdalene sees the risen Jesus and mistakes him for a gardener.  (John 20:11-18)  In fact, he is a gardener.  In his death and resurrection, Jesus restores the creation as just the place where the Kingdom of God will grow and flourish.  He has turned dirt into Kingdom Soil.
That’s you.  That’s me.  That’s the sorehead you don’t want to sit next to at lunch and the neighbor whose dog barks to greet the sun…for hours.  God is doing something with us.  He’s growing his kingdom.  We’re just the soil he wants.
(This image above is Piero della Francesca’s fresco The Resurrection found at http://www.themennonite.org.)