When you are a kid, you dream of the day that you have enough money to buy anything you want. Then, you grow up and have money and realize that you can buy everything that you want but you realize that it is more wise to only buy everything that you need. You still want things but you realize that not everything benefits you. You can buy the whole candy or snack aisle at the grocery store but you know what will happen later so you don't do it. Our desires are different WHEN we delight in God. The "Delight yourself in the Lord" portion of this verse is essential. That is why it is there and that is why it is first.
Lord, thank you that my desires are more in line with Your desires and when they are, you give generously.