The lack of gratitude displayed in this passage reveals a deeper heart issue. Moses delineates all the things that God has done for Israel in the past, both material and spiritual. God brought them out of slavery, protected them from the serpents and scorpions in the wilderness, provided water for them in miraculous ways, gave them food from heaven which no one else has ever known, kept their clothing from wearing out, prevented their feet from swelling (indicating dehydration and heat stroke), and then gave them power to get wealth (vv. 3–5, 15–18). Not only that, but Moses describes the good land that God is giving them, including all the water that is present (unlike the wilderness) and the plants and trees and fruit that they have not had in the desert (vv. 6–10). Wheat, barley, vines, fig trees, pomegranates, and olives all require significant amounts of water and irrigation. These are luxury items that Israel has not had in the desert. In addition, there will be good houses and many flocks, and they will have silver and gold, and multiplication of possessions (vv. 12–14). When considering all these things, it is hard to understand why Israel would not be grateful. But for all sinful humans, it is easy to forget what God has done in the past, and easy to look at life as relying on our work to get anything good to happen.
And yet, anything good is always from God. The reason we are alive is because of God. The word of God to our hearts is more important than physical food. And a humble, teachable attitude is more important than material blessings. God disciplines us like a good parent who wants the best for His children, recognizing that pride of heart is the root of all evil (v. 14). The end result is always good when God brings us to a place of testing and humility (v. 16). God wants us to live and not die!
This is a reiteration of the heart of the covenant, remembering God and reflecting on all He has done, and blessing Him for His provision for us. While we may not eat of literal manna today, we can all relate to the hard times Israel has been through, and look for how God has sought to provide for and humble us as well. We can ask God to teach us as He did Israel, so that our hearts may be soft toward Him.