Smallville, Season 5

Clark:
Am I dead?

Jor-El [in Lionel]:
Your mortal journey is over, yes, but your eminent destiny is too important to sacrifice. You will return with all your natural gifts. Unfortunately, this rectification does not come without a price. The life of someone close to you will be exchanged for yours.

Clark:
No. No, I would never ask for that.

Jor-El [in Lionel]:
You already did. When you decided to relinquish your powers and disobey me. It was your choice.

Clark:
Then just don't bring me back!

Jor-El [in Lionel]:
It's too late. For everything in nature, there is a balance. The life force that has been returned to you will soon be taken from... from someone you love. You're about to face your darkest hour, my son. But, remember: The lessons that we learn from pain are the ones that make us the strongest.