Jesus can be referred to as “a god” even though he is not God Almighty for the following reasons:
http://m.wol.jw.org/en/wol/d/r1/lp-e/1200001729?q=ps+82%3A6&p=par#h=10...
The judges of Israel were called “gods”. At Psalm 82:1, 6, ʼelo·himʹ is used of men, human judges in Israel. Jesus quoted from this Psalm at John 10:34, 35. They were “gods” in their capacity as representatives of and spokesmen for Jehovah.
Moses was told that he was to serve as “God” to Aaron and to Pharaoh.—Ex 4:16, ftn; 7:1...again because he was a spokesman for God.
JESUS identified his role and his relationship with his father at John 10:31-36. The Jews wanted to stone him. Jesus asked them why. THEY charged he was claiming to be a god, or claiming to be god (depending on the translation you use). Jesus replied by reminding them that they (the judges of Israel) were called “gods” in scripture (and then reminded them that scripture cannot be nullified). (Jesus was quoting from Ps 82:1,6.) So since THE JUDGES OF ISRAEL WERE CALLED GODS themselves, how could they stone him just for saying he was GOD'S SON?
At Isaiah 9:6 Jesus Christ is prophetically called ʼEl Gib·bohrʹ, “Mighty God” (not ʼEl Shad·daiʹ [God Almighty], which is applied to Jehovah at Genesis 17:1)."
Jesus, even though God's son could prophetically be called a Mighty God because he was:
a) Jehovah Gods spokesman (John 7:16,17)
b) Appointed to become judge to all those who lived on earth. (ACTS 10:42)
So, in summary, since Jehovah God referred to Moses and Israelite judges as "gods" in scripture, Jesus most certainly was a mighty god.