In this chapter, Moses reiterates the blessings of the LORD and obedience that is demanded of the Israelites.
In broad terms, this chapter is about humility and pride. In verses 1-6 Moses explains that the journey through the wilderness was a test to establish the humility of the Israelites. Verses 7-10 establish the goodness of the promised land with a result that "you shall bless the LORD your God". Verses 11-14 show that if the people forget God, then they will think all these things are the work of their own strength and rise up in pride. Verses 15-20 show the results of these two attitudes. On one hand, the people might say "my power and the strength of my hand made me this wealth", and on the other hand they would know that "[God] is giving you power to make wealth".
The general framework of this chapter is to show a few things. It shows that the Israelites will soon pass into a land of extreme wealth. We have already seen this principle a few times, such as Num 13 and more recently in Deut 6:10-12, but this chapter is even more lustrously detailed.
As a result of this new wealth, Moses warns of two possible outcomes. The Israelites can either recognize that the LORD is the source of their wealth, or think that they created it themselves. As a result, they will either "bless the LORD" in humility, or become prideful in their hearts and be swept away in destruction.
Another part of the framework is the repeated emphasis on the humbling process in the wilderness (which is stated first in v. 2-3 and second in v. 16).
Put together, we can see that there is an intended testing process in poverty, and there is a distinctly different test that occurs when obtaining wealth.
Beginning with the wilderness journey, Moses emphasizes the Israelites' dependence on the LORD through the consumption of manna. Manna was the bread that the LORD provided to feed the Israelites throughout their years in the wilderness. As such, it is a symbol of the Israelites' helplessness and dependence upon God. Without manna, they would have died, and manna was completely beyond their power or ability to influence or create. That's why Moses says God gave the manna to humble them, because it put them in a position of total dependence.
It tested them, whether they would depend on the LORD and accept that humility. Having read through both Exodus and Numbers, I think we can agree this is a test they broadly failed over and over. Yet here we are, the Israelites are still alive and about to enter the promised land. I think their repeated failures are a concerning sign for their future in light of this chapter.
In emphasizing the humility of the desert journey, Moses says one of my favorite lines from the entire bible, verse 3: "He humbled you and let you be hungry, and fed you with manna which you did not know, nor did your fathers know, that he might make you understand that man does not live by bread alone, but man lives by everything that proceeds out of the mouth of the LORD."
This is really a great verse for a couple reasons. First, it captures the humility and dependence aspect I was just talking about. Second, it draws a parallel between the Israelites' dependence on manna an our dependence upon every word that comes from the LORD. Narrowly constructed, this refers to the Pentateuch. Broadly constructed, it refers to everything that the LORD says in the scriptures and even beyond the scriptures. The word of the LORD is even equated with food, something without which man cannot survive. It's not just the Israelites who depend on it, everyone depends on it.
Third, this verse also gives us an interesting new perspective on bread. Since bread is equated with the word of the LORD, we can read other passages that include the usage of bread and see if a metaphorical rendering provides any more insights. One place that comes to mind is the "table of showbread" which is first described in Ex 25:23-30 (my commentary here) and elaborated further in Lev 24:5-9 (commentary here). It is a table within the holy place of the tabernacle, on which the Israelites were commanded to place bread every Sabbath, so that it would continually hold fresh bread. It is one of the three "continual" symbols in the tabernacle, with the other two being the continual incense and the continual burning lampstand.
Verse 3 gives us some insight into the continually offered bread. It is probably meant as a reminder of the Israelites' perpetual dependence on the LORD, both for physical and spiritual needs, as man requires the manna, material provision, as the words of the LORD, spiritual provision.
So that's one way to look at the desert journey, as an example of man's dependence on God. The other way to look at it is an example of God's faithfulness to man. Unless God provided manna every day, the Israelites would have died. But God was with them and fed them every day for 40 years.
And those are the two sides of the covenant; man's need and God's faithfulness.
So that's the testing process that comes with adversity. It is a test of humility, whether people can accept their dependence on God and trust in his faithfulness.
The second test is a test of wealth. In this case, the Israelites are challenged not with adversity, but with prosperity. This isn't something that is normally considered a challenge, but the author makes it clear in this chapter that he does. The challenge is that, in prosperity, the Israelites might forget their dependence on God and think that the wealth they possess is the result of their own power. This leads to another fabulous passage, v. 17-18: "... you may say in your heart, 'My power and the strength of my hand made me this wealth.' But you shall remember the LORD your God, for it is he who is giving you power to make wealth..." Every blessing that the Israelites possess is a result of divine providence through the covenant. The test of wealth is a challenge to remember the LORD even when we don't think we need him.
In the wilderness, all the Israelites knew they needed the LORD because of the manna. In the promised land, they are able to live by their own hands, and so they risk thinking that it is their hands which provide for their needs. They are challenged to remember that the power to create wealth is being given to them by the LORD, so the appearance of depending on the LORD is gone, but they still depend on the LORD just as much as in the desert.
Lastly, from a literary perspective I really enjoy verses 15-16 as a description of the Sinaitic desert. While this is certainly a poetic description and probably a bit hyperbolic, I think it really gives us a good idea of how harsh and dry the wilderness really is. I especially like the imagery of drawing water "out of the rock of flint", which contrasts the life-giving nature of water with the harsh, unforgiving hardness of a rock. The "rock of flint" is symbolic of the larger wilderness (which would have consisted of many rocks), while the water drawn forth is symbolic of the LORD's provision for the Israelites in their time of need. In some ways drawing water from a rock is a metaphor for drawing life out of death. I have written at other times about this miracle, so I won't go into more depth here.