From the Archdiocese of Melbourne, Australia's Life, Marriage and Family Life Office:
Presently our Federal House of Representatives is considering proposals that would redefine marriage to include same-sex couples. As our bishops have reminded us, our society is now at a critical turning point where truth is at stake. Our views are being sought by the Australian Parliament. It is important that we take this opportunity to express support for marriage between a man and a woman.
The points below are offered to assist you in responding to the inquiry.
... While affection between a married couple is important, those feelings alone do not provide a sufficient reason for governments to be involved. Regulating matters of the heart is not the business of the state. Rather, it is precisely because of the natural link between the intimate relationship of man and woman with bearing and nurturing children – the future citizens on whom society depends - that legislators should continue to recognise and protect our current definition of marriage.
... Decades of social research bears witnesses to the fact that children are best served when raised in the home of their biological parents. While this may not always be possible, it is no reason to discard the ideal which has served societies for thousands of years.
... Attempting to call “equal” a form of relationship which by definition must deprive a child of his or her relationship with one or both of their natural parents, denies children their rights.