"Danger, The Spur Of All Great Minds"

Context: Clermont, the brother of the dead Bussy D'Ambois, and the Duke of Guise enter. The duke tells Clermont of a voice that spoke to him in the heat of a battle. Clermont says that it was only a waking dream, as the imaginary power of the mind or the vapors of humors present illusions so convincingly that they seem real. Guise, however, is of the opinion that such things are portents of weighty and secret events to come. The news he has received from abroad convinces him that his plot for the furtherance of Catholicism will prove to be bloody. Upon Clermont's advising him to abandon the plot if there will be so much bloodshed, he replies that to do so would be the abandoning of France. Clermont says to let fall everything that is unlawful and do not in the name of religion indulge in vice. By being virtuous and religious the duke can accumulate grace without running into danger. At this point the ghost of Bussy D'Ambois appears to Clermont alone and remains invisible and inaudible to Guise. He speaks so that only Clermont can hear him:

Danger, the spur of all great minds, is ever
The curb to your tame spirits; you respect not,
With all your holiness of life and learning,
More than the present, like illiterate vulgars.
Your mind, you say, kept in your flesh's bounds,
Shows that man's will must ruled be by his power,
When by true doctrine you are taught to live
Rather without the body than within,
And rather to your God still than yourself;
To live to Him is to do all things fitting
His image, in which like Himself we live:
To be His image is to do those things
That make us deathless, which by death is only
Doing those deeds that fit eternity;
And those deeds are the perfecting that justice
That makes the world last, which proportion is
Of punishment and wreak for every wrong,
As well as for right a reward as strong.
. . .