Genesis 8:21

And the LORD smelled a sweet savour; and the LORD said in his heart, I will not again curse the ground any more for man's sake; for the imagination of man's heart is evil from his youth; neither will I again smite any more every thing living, as I have done.

1. Recognizing Noah's burnt offerings, the Lord decided He would no longer curse the ground for man's sake, nor would He again kill every living thing as He did via the flood.
2. People feel like doing evil things from the time they are young.
3. I suppose its possible the Lord actually smelled the burnt offering, but I'm more inclined to consider it imagery for the following reasons: 1) The Lord, who is Christ, was only a spirit at this point and didn't have a physical nose with which to smell. Can a spirit smell burning meat? 2) The Lord would have to have been fairly close by to smell the burnt offering, like in the same neighborhood. Is the Lord in the habit of wandering around upon the earth? Perhaps, but that contradicts the notion that He resides in heaven, unless that's also on earth.
4. If the Lord said these words in His heart, how is it someone wrote them down, unless He also spoke them to someone?