Was as an enemy: he hath swallowed, etc. The threefold division of the verse is, unfortunately, concealed in the Authorized Version, owing to the arbitrary stopping. The grouping suggested by the Massoretic text is—
"The Lord is become an enemy, he hath swallowed up Israel;
He hath swallowed up all her palaces, he hath destroyed all his strongholds;
And hath increased in the daughter of Judah moaning and bemoaning."
The change of gender in the second line is easily explicable. In the first case the poet is thinking of the city; in the second, of the people of Israel. The rendering "moaning and bemoaning" is designed to reproduce, to some extent, the Hebrew phrase, in which two words, derived from the same root, and almost exactly the same, are placed side by side, to give a more intense expression to the idea.