And as she looked about, she did behold
How over that same door was likewise writ,
Be bold, be bold, and everywhere Be bold,
That much she mused, yet could not construe it
By any riddling skill or common wit.
At last she spied at that room’s upper end
Another iron door, on which was writ,
Be not too bold.

Edmund Spenser (c. 1552-1599) English poet

The Faerie Queen, Book 3, Canto 11, st. 54 (1590-96)
    (Source)