Organ donation is an amazing thing, but recipients of organs often need to be in fairly good shape to get them.  Amazingly, God found us in terrible shape but still gave us an organ donation. He says, 

"I will cleanse you from all your filthiness and from all your idols. Moreover, I will give you a new heart and put a new spirit within you; and I will remove the heart of stone from your flesh and give you a heart of flesh." (Eze 36:25-26)

We've been given a new heart and a fresh start. If we go back to the same things and lifestyle that made us sick, instead of working to grow stronger, we can risk wasting that new heart. Let's recognize how precious this new heart is and grow stronger every day, taking care of this gracious gift we've been given.