What is "very God of very God"?

Is there anything wrong, when seeking to defend the real Deity and true humanity of our Lord, in making use of the statement, “He is very God of very God, and very Man of very man?”

The words, “very God of very God” were inserted in the creed of the Nican elders and teachers at the council of Nica in A.D. 325, for whose faithful contending for the faith we may well thank God. They were intended to safeguard the true Deity of Christ, in opposition to the soul-destroying heresies of Anus, which denied it. They affirmed that the Son, though truly said to be the only begotten of the Father, is no less truly God—co-equal, co-substantial, and co-eternal with the Father and the Spirit. The creed, like every human writing must be tested by the Word of God. In this case, I judge, the expression in question to be quite legitimate and laudable. But the expression, “very Man of very man,” stands on other footing. It does not, for one thing, occur in the Nicene creed, nor, as far as I know, in any other, and in my judgment ought to be avoided. It is an attempt to express “the secret things” of the Incarnation, but seems to ignore the part the Holy Spirit had in the conception—”That which is conceived in her is of the Holy Ghost.” We must and do insist on the true humanity of our Lord, but without attempting to define how it was produced.