John Calvin Commentary Leviticus 26:39

"And they that are left of you shall pine away in their iniquity in your enemies` lands; and also in the iniquities of their fathers shall they pine away with them." — Leviticus 26:39 (ASV)

And those of you who are left. This is another form of vengeance: although they may survive for a time, still they will gradually pine away. This can be referred both to those who go into captivity and to those who will remain in the land.

He had previously threatened that they would be destroyed either by famine or sword. But now, lest they should boast that they had escaped if they had not perished by a violent death, He pronounces that they also will die a lingering death. He also declares the manner of it: namely, that He will fill their hearts with trembling, so that they will flee when no one pursues them (as Solomon also says, Proverbs 28:1) and fear at the sound of a falling leaf.

Thus He signifies that the ungodly will be no better off, although free from external troubles, because they are afflicted internally by hidden torments. For although their audacity may proceed even to madness, still their evil conscience will inevitably smite them continually.

Their forgetfulness of God may sometimes stupefy them; indeed, they may seek to shake off all feeling. But after God has allowed them to become brutalized in this way, He soon interrupts their lethargy and hurries them on, so that they become their own executioners.

This passage shows us that the more hardened the wicked are in their contempt of God, the weaker they become, so that they tremble at their own shadow. This condition is far more wretched than to be cut off by a single blow.