The reason that women are not to be ordained is because they are not men. Sounds politically incorrect, doesn’t it? But the fact is that God created men to be men and women to be women. When God chose to incarnate, he did not just choose to become a human being; he chose to become a man. Just as he chose to incarnate into a specific time, place, people, family, and woman, so he chose to become a specific human being, the man Christ Jesus (1 Tim. 2:5). Thus, those human beings who serve as priests in the person of Christ are men and not women.
This shocking particularity of God is not limited to choosing men to become priests. To demonstrate this to proponents of women’s ordination, you might turn the question around and ask them what it is about men that makes them unfit to bear children. Surely a man is just as physically strong as a woman and psychologically and emotionally capable of the demands of giving birth. Surely he is not inferior to a woman. Isn’t it unfair to men that only women can have babies?
This line of logic descends into absurdity, because women having children is a natural fact of life, something easily seen and understood. To shake one’s fist at the heavens and demand equal rights for men to give birth is to rail against the natural order. At that point you can establish that men being priests is a supernatural fact of life, and to object to it is to object to the supernatural order. The fact that the supernatural order cannot be seen and is not as easily understood as the natural order does not mean that the supernatural order does not exist.