Let's resume:
The Winchester boys are human. They eat, sleep and make mistakes while they keep on fighting the evil. And their loved ones either get hurt for them, or become better people by their hand and cause.
Castiel is an angel. No, he was an angel. Castiel is a humanized angel. He never eats, sleeps, or gets a head full of corrupted and tempting thoughts unless his reserve for angel grace is low; that is not seldom.
Marry Winchester is the reason the viewer starts the series and continues, and she is a true example of the human kind in this age, that experiences thick sadness and feels like ten kurush (a dime) waiting for change, while on track to reach and achieve goodness.
Bobby Singer is the ideal mix of everything that is to say, ranging from a lovingly cursing uncle to a blaster-like monster hunter!..
Lucifer! We can never know how Satan fares with this portrayal by Mark Pellegrino other than we may believe how the real Satan will do evil in keeping with our own cultural heritage. Boy, is he not successful!..
Jack is... something else. The actor playing Jack, that is mr. Alexander Calvert, gives away this humane vibe out of his juvenile, upright form that's about to be imprinted onto our hearts somehow.
He's the future to this show, we feel. Even after the show ends, he can act in the Supernatural Universe with the Wayward Sisters, who are to step into this game with a sound stroke, thanks mostly to ms. Kim Rhodes (Sheriff Jody Mills) and ms. Kathryn Newton (Claire Novak).
This episode reminds us of the way Supernatural operates. Angels, demons, monsters, humans and the faculty of free will backed with the guiding spirit of reason, heart and revelation... and the war to reign over all in between them.
The writers can still grasp the rippled structure of the human kind which paves the way for this linear flat called life. Supernatural is the life.
Here is two Verses of my culture:
"-And when there cometh unto them a messenger from Allah, confirming that which they possess, a party of those who have received the Scripture fling the Scripture of Allah behind their backs as if they knew not,
-And follow that which the devils falsely related against the kingdom of Solomon.
Solomon disbelieved not; but the devils disbelieved, teaching mankind magic and that which was revealed to the two angels in Babel, Harut and Marut.
Nor did they (the two angels) teach it to anyone till they had said:
'We are only a temptation, therefore disbelieve not (in the guidance of Allah).'
And from these two (angles) people learn that by which they cause division between man and wife; but they injure thereby no-one save by Allah's leave.
And they learn that which harmeth them and profiteth them not.
And surely they do know that he who trafficketh therein will have no (happy) portion in the Hereafter; and surely evil is the price for which they sell their souls, if they but knew."
The Gracious Koran: 2 (The Cow) : 101 - 102.