Soren Kierkegaard wrote, ". . . to be anxious for the next day is covetousness." This is found in "The Anxiety of Self-Torment." Think about it. It is a powerful message. To be anxious about other than today is to have a "feeling or showing a very strong desire for something that you do not have and especially for something that belongs to someone else," which is how Merriam-Webster defines "covetous." You can mull this on many levels. Tomorrow we do not have. To whom does tomorrow belong? (For that matter, can't we ask the same questions of today?) It's as if Kierkegaard is saying, "Don't be greedy. You have enough to worry about today. Don't borrow tomorrow's troubles." (I recognize that "greedy" differs in meaning from "covetous.") Still, there's a lot there to chew on. Isn't there? Just for today.