The angel’s nature then is rational, and
intelligent, and endowed with free-will, changeable in will, or
fickle. For all that is created is changeable, and only that
which is un-created is unchangeable. Also all that is rational is
endowed with free-will. As it is, then, rational and intelligent,
it is endowed with free-will: and as it is created, it is
changeable, having power either to abide or progress in goodness, or to
turn towards evil.