The following is from Martin Saunders. I could not of said this nearly as well as he has so I leave it to him.
If you're looking for an inspirational, heart-warming verse in the Bible, they don't come much more Hallmark than Jeremiah 29:11
It's one of the most popular verses in the Bible, bringing comfort to millions every day. It's a wonderful, warm sentiment, which has spawned a veritable industry of bookmarks, posters and mugs. It is pinned to refrigerator doors all over the world, a source of daily encouragement that 'God is in control.' Most Christians will know it well:
"For I know the plans I have for you, says the Lord. Plans to prosper you and not to harm you; plans to give you a hope and a future" (Jeremiah 29:11).