(Divine). The divine Althea of Richard Lovelace was Lucy Sacheverell, called by the poet, “Lucretia.”
When love with unconfined wings Hovers within my gates, And my divine Althea brings To whisper at my grates.
The “grates” referred to were the prison grates. Lovelace was thrown into prison by the Long Parliament for his petition from Kent in favour of the king.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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