Well, folks need to read all the way to and through verse 19 where God CONTINUES his promise. And it starts with “BUT”. ... and goes on to complete the negative consequences side of His promise.
‘But if you don’t do all that I will re-scourge you.’ (paraphrasing)
You can’t ‘claim’ half of a promise from God.
He said ‘if you do this, I will do that. But if you don’t I will come down on you even harder.’ II Chron 7 is a good chapter to read ALL the way through.
It IS one of my faves.
The Bible is full of “ifs” “ands” and “buts!”