The image of this perfect mind is very beautifully designated by the centurion in the Gospel. His virtue and steadfastness did not let him be led astray by the thoughts that assailed him but, in accordance with his judgment, he admitted the good ones and drove away the opposing ones without any difficulty…”I also am a man under authority, having soldiers under me, and I say to one: Go, and he goes; and to another: Come, and he comes; and to my slave: Do this, and he does it.” If we also, struggling manfully against disturbances and vices, are able to subject them to our authority and discretion and, warring in our flesh, can extinguish our passions, subjugate the unstable cohort of our thoughts to the rule of reason…as a reward for such triumphs we shall be promoted to the rank of this spiritual centurion…Thus, raised to the height of this dignity, we also shall have this power and strength of command, so that we may not be led astray by thoughts that we do not want but may be able to remain in and cling to those by which we are spiritually delighted, commanding evil suggestions to go, and they will go, but telling the good to come, and they will come.
~St John Cassian (Conferences 7.5 p.251)
Prayerful Life 