well Socrates put the virtues to a very thorough examination. I'm a little fuzzy on this as we have only just started to study some of what he said but what sticks in my mind is that he likened himself to midwife - never really giving birth himself but helping others to do so.
I think he would say that it is necessary for "God" to be good so that there may be an ideal of goodness for humans to reach for. However, Socrates himself, I think, would question conventional ideas about god as he tended more towards atheism. But as to what goodness actually is, this would have to remain an open question because goodness does incorporate polarities (I don't think that Socrates would agree with me though as he tended to wonder that there may be an ultimate form of goodness).
Overall I agee with those who say the deity is beyond definition.