HOLY SPIRIT: WHO ?

Hubble Heritage
http://www.spacetelescope.org/images/opo0428a/

The mystery of the Eloheyem family is very great. John reveals in his gospel that Yeshua is the Eternal Logos. 

(Jn 1:1-3) Logos existed with the Heavenly Father and together; they created everything. 

(Jn 1:14)  Logos entered the physical creation by becoming human. It is revealed that he is the one and only Son who comes from the Father. (Jn 10:30) The Eloheyem family consisted of only two persons. So who or what is the Holy Spirit?