Warfare — The time of her captivity, and misery. Double — Not twice as much as her sins deserved, but abundantly enough to answer God's design in this chastisement, which was to humble and reform them, and to warn others by their example.
Related Commentaries of Isaiah 40:2
Isaiah 40:2
2 Speak ye comfortablya to Jerusalem, and cry unto her, that her warfare is accomplished, that her iniquity is pardoned: for she hath received of the LORD'S hand double for all her sins.