Albert Barnes Commentary Isaiah 49:19

"For, as for thy waste and thy desolate places, and thy land that hath been destroyed, surely now shalt thou be too strait for the inhabitants, and they that swallowed thee up shall be far away." — Isaiah 49:19 (ASV)

For thy waste and thy desolate places - Your land over which ruin has been spread, and over which the exile nation mourns.

And the land of thy destruction - That is, your land laid in ruins. This construction is not uncommon where a noun is used to express the sense of an adjective. Thus in Psalms 2:6, the Hebrew phrase (margin) is correctly rendered my holy hill. Here the sense is that their entire country had been so laid waste as to be a land of desolation.

Shall even now be too narrow - It shall be too limited to contain all who shall become converted to the true God. The contracted territory of Palestine shall be incapable of sustaining all who will acknowledge the true God, and who shall be regarded as his friends.

And they that swallowed thee up - The enemies that laid waste your land, and that absorbed, as it were, your inhabitants, and removed them to a distant land. They shall all be gone, and the land shall smile again in prosperity and in loveliness.