Simple Logic

Given that this question seems to have come up again, I would like to at least express what I believe to be a simple orthodox position. It might not convince everyone, but it is a position which is held in the spirit of charitable enquiry.

1) Empirical Fact: Every human being requires two gametes in order to gestate and come to birth: a sperm and an ovum.

2) Definition: The provider of the sperm is called the father of the child.

3) Definition: The provider of the ovum is called the mother of the child.

4) Empirical Fact: The gestation of the child occurs in the womb of the one who provided the ovum who then proceeds to give birth to the child.

5) Lemma: The mother gives birth to the child.

Proof 

Follows directly from (3) and (4).

6) Lemma: Jesus is fully human

Proof 

"The Word was made flesh" plus the Nicene Creed.

7) Lemma: Jesus is male in His human nature.

Proof 

This follows from St Luke ii.21ff, in which Mary and Joseph follow the Mosaic Law for presenting a first born son. The New Testament is unequivocal in referring to Jesus as a man, as are even the apocryphal gospels.

8) Lemma: Joseph is not the father of Jesus. 

Proof

The Gospel narratives of the infancy of the Lord are in concordance.

9) Lemma: Jesus is the Son of God.

Proof 

The Nicene Creed among other things.

10) Lemma: Mary is the mother of Jesus

Proof

See the infancy narratives of the Gospel plus the Council of Ephesus in which Our Lady is proved to have the title Theotokos.

11) Lemma: Jesus had a biological father

Proof

From (6), Jesus is fully human.

From (1), Jesus required two gametes for His gestation.

From (10) Mary is Jesus' Mother.

From (3) Mary did not provide the sperm.

 Therefore someone else provided the sperm.

From (2) this someone else would be the father of Jesus.

12) Lemma: The Divine Person who begat Jesus is properly termed Father and thus is rightly referred to in male terms.

Proof

From (11) Jesus had a biological father.

From (8), this was not Joseph.

From (10), this was not Mary.

From (9), this biological father was God.

Excursus 

Objection: The Holy Ghost is fully God and is described with the feminine gender.

Reply to objection

Both the Hebrew and the Greek words for "spirit" are grammatically feminine. The Greek word for table (trapeza) is also feminine. It is conceivable that by allowing his small children to rest their toy tea set upon his back, a father can be a table. Thus grammatical gender is not determinative of the identity of the person to which it refers.

It is therefore possible for the Holy Ghost to be referred to in male terms of identity despite being grammatically feminine.

Since the Father and the Son are to be referred to in male terms of identity, both being fully God, the Holy Spirit too, being fully God, should be referred to in male terms.