where did the bad angel come from?

Sonnet 144

Two loues I haue of comfort and dispaire,
Which like two spirits do sugiest me still,
The better angell is a man right faire:
The worser spirit a woman collour’d il.
To win me soone to hell my femall euill,
Tempteth my better angel from my sight,
And would corrupt my saint to be a diuel:
Wooing his purity with her fowle pride.
And whether that my angel be turn’d fiend,
Suspect I may, yet not directly tell,
But being both from me both to each friend,
I gesse one angel in an others hel.
Yet this shal I nere know but liue in doubt,
Till my bad angel fire my good one out. *


The angel is good man, the woman is evil, no problems there, but where does the bad angel (last line) come from? Perhaps we'll never know, but live in doubt.

Ideas anyone?