Ophiuchus is the 13th sign.  13 is the sign of rebellion, but also redemption - the prodigal number.  He is the "serpent bearer" and victor over death...

 

http://earthsky.org/tonight/sun-in-ophiuchus-november-30-to-december-17

 

Who is Ophiuchus:  http://en.wikipedia.org/wiki/Ophiuchus

 

His sign is the one that we now see w/ Physicians.  It is the one Jesus quoted regarding himself & Moses:

 

John 3:14 (King James Version)

 ¹⁴And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up:

(Read all of John 3, which is Jesus' commentary about being "born again" to Nicodemus.  Also John 3:16 and John the baptists line "I must decrease and he must increase.")