Then he said to them, "Watch out! Be on your guard against all kinds of greed; life does not consist in an abundance of possessions."
Read this verse in its context. It starts with a man coming to Jesus and asking Jesus to resolve a dispute he had with his brother about his inheritance. Jesus basically says he’s not going to do it, and tells the man that he’s got his priorities wrong. He loves money rather than God. Jesus goes on to tell a story, a parable, of a man who was blessed with a good harvest. Instead of thanking God for the great harvest, he decides to put his faith in his wealth. His plan for the future is in his wealth, not in God. He tears down his barns, builds bigger ones, and then says with great assurance that he can now take life easy. However, before he can get there, he dies. His faith in his wealth brought him nothing.