The way that God words His promises (and threats) to Israel does not ring well in the ears of coddled Americans who have been fed a steady diet of self-esteem philosophy. God wants to see Israel succeed as a nation not for their good feelings exclusively, but for His great glory. He will reward them for faithfulness to the covenant (first part of Leviticus 26) and punish them for breaking His laws (the last part of the chapter). And when and if they repent from failure, He will restore blessings because HE MADE A COVENANT with their forefathers. That is the part the stings to those of us steeped in feel-good self-esteem thinking. Basically God is saying, “Thanks for turning to me. I’ll reward you because your grandparents made a covenant with me.”
The success that Israel enjoyed clearly was held by God. They would be expected to follow the Law and keep God’s commands. But they were only getting blessing from God, not from their obedience alone. It was not formulaic. It was spiritual. It all depended upon God, which is why He got the glory. And they were to realize that they would be content in being a people who lived for His glory.
So God is not really into handing out trophies for our performance. The same is true for me. All I am is a result of the redeeming work of Christ. I get no credit. God gets the glory. My purpose is to bring glory to Him!