A free slave??

I'm a slave of Yeshua(Christ). And yet I'm free. (Romans 6:18-22)
How does that sound to you? Is it hard to make sense of this?
How can you be free and a slave at the same time??
I like using a story about Abraham Lincoln to explain.

Before the Civil war and ambolishing slavery in many U.S. territories as president.
Abraham made an example by going down to the docks where slaves were brought in off the boats and auctioned off. He went with the plan to purchase one.
A beautiful black woman was up to be auctioned. Abraham decided to bid on this slavegirl. Many other bidders were also interested in this beautiful slave but Abraham would always up there offer by a dollar, until he eventually won her. He got up on the dock to approach this young, disheartened, head hung low woman. He asked the previous owner to unchain her. She looked up and asked him "what do you intend on doing with me?"
"You are free", he announced.
Puzzled she answered "excuse me?"
Abraham replied "You are free to go wherever you want, to do whatever you please, you are free."
With everyone's shock, especially that of the young woman. Falling on her knees, she replied with great happiness, "Well if I am free, I want to go with you!"
Abraham now puzzled asks, "I just set you free, free to be whatever you want, go wherever you wish, why would you want to come with me?"
"I want to be with the man that set me free!" she responded.

You see, though she was set free, she bound herself to the man that set her free. She knew the awful situation she was in. If she were to just shrug and say "okay" and walk away like it was no big deal, then she probably didn't need to be saved in the first place! But because she understood and realized the depravity of her situation, she was so thankful to be released from it.
This is how it should be with Yeshua(Christ). He saves us from our depraved nature, and those who are truly thankful for this, bound themselves to him, working to please him with a thankful heart.
First we need to realize how enslaved to sin we are, how corrupt, evil and lost we are. So the freedom that is offered by Yeshua(Christ) our Lord, will be taken and recieve with a sincere and yearning heart.
Lets not be someone who just shrugs, says "okay" and walks away as though it was nothing.
FREEDOM IS FOUND IN HIM!

(I don't know if the story above is a true story or merely fictional. Don't remember who I heard if from)