This passage relates various works of the Most High's providence, but it carries a negative tone because of the people's unbelief and distrust. God blessed Israel with water in the desert, manna every day for forty years, and everything else that they needed. This was after He had delivered them from Egypt, led them between walls of water, and destroyed the might of the world's greatest empire. The people, though, would not believe that the Possessor of heaven and earth would govern His creation favorably for them! They would not believe because He was not real enough to them.
Do we believe? Do we trust in the salvation process that the Most High is leading us through? Do we believe in His deliverance? Do we believe in His ability and willingness to bless us with whatever we need to be a part of His Family—even to the point of providing a perfect sacrifice to take away our sins? Is there any righteous work that He will not perform or any good thing He will not provide for His people?
Do we trust in His nature and His unassailable character? Israel did not, and as a result, provoked the Most High to wrath. They created their own self-fulfilling prophecy. Because they did not believe God, they believed that things would turn out badly, and in not believing Him, things turned out badly!
In the same way, those who tend toward pessimism usually prove themselves right because the pessimism clouds their view of God and thus their belief of and trust in Him. When that happens, as with Israel, they run the great risk of provoking Him to wrath. People see either God or the negatives, and whichever one they see determines their trajectory.