Marriage is the Foundation of the Family.

"Family is the first vital cell of society; the first church, first school, first hospital, first economy, first government and first mediating institution of our social order. Heterosexual marriage, procreation, and the nurturing of children form the foundation for the family, and the family forms the foundation of civil society.

"Marriage as existing solely between one man and one woman was not an idea manufactured by the Christian Church. It precedes Christianity. Though affirmed, fulfilled, and elevated by Christian teaching, the truth that marriage can exist only between one man and one woman is not based on religion or revelation alone, but on the Natural Moral Law, written on the human heart and discernible through the exercise of reason."

Source: Supreme Court Stays Redefinition of Marriage in Virginia.