John Gill Commentary Leviticus 26:18

"And if ye will not yet for these things hearken unto me, then I will chastise you seven times more for your sins." — Leviticus 26:18 (ASV)

And if you will not for all this hearken to me
If such corrections by diseases of body, and by giving them up into the hands of their enemies, should be ineffectual to reform them and bring them to obedience to the statutes and commandments of God, but should continue in their disobedience and rebellion against him: then I will punish you seven times more for your sins ;
that is, abundantly more, with sorer punishments, and these more frequently repeated.