Reverend Rob Schenck, president of the National Clergy Council, says the model of heterosexual marriage works, and should be protected:
A constitutional amendment to protect traditional heterosexual marriage is the right way to end this contentious issue. While some may legitimately criticise any attempt to tamper with the Constitution, a runaway and recklessly activist judiciary has left no option.
President Bush is right in urging Congress to act on such an amendment and to do so quickly. This is a delicate matter because it is fraught with possible misunderstandings as to motive and outcomes.
Some wrongly say that the president's motive is political. Nothing could be further from the truth.
Taking on a social controversy of this magnitude could not be better than leaving it alone. The fact is that social conservatives have nowhere else to go than to Mr Bush.
I believe the president's actions stem from his sincere concern over the dangers of abandoning the tried and true configuration of one-man one-woman monogamous family unit.
Others say that granting a special constitutional protection of marriage leaves any sort of state sanctioned civil unions in a "different," even inferior second-class status. (The Massachusetts Supreme Court among them.)
The reality is, though, that such "civil unions" are very different than marriage. It is the complement of male and female - physically, bio-chemically, psycho-socially - that makes marriage unique. These elements cannot be duplicated in same-sex relationships.
The two-parent family has never responded well to experimentation. We have had plural marriage in America and the result was unquestionably problematic for everyone involved. We have had government subsidies of single-mother households and the results have been catastrophic.
What will it take for us to get the message? The model of heterosexual marriage works; in fact, it works superbly.
Judges and justices ill-informed and perhaps even entertained by social experimentation should not be allowed to meddle with something so important to social stability, child development and the continuance of a species.
Billions of billions of human beings over millennia of time and in virtually every culture couldn't be all wrong. We need this amendment to protect the sanctity of marriage and we need it now.
Kevin Cathcart, executive director at Lambda Legal which works for legal rights for lesbian and gay people in the US, says the Constitution should be for all Americans:
A proposed amendment to the US Constitution that President George W Bush announced his support for this week would take away critical rights and protections from hundreds of thousands of families nationwide.
It would even block them from seeking such protections through the nation's centuries-old democratic process.
Same-sex families pose no threat to this country or to other couples.
The threat to families is a proposed amendment, which would actively add discrimination into the Constitution for the first time ever.
Our Constitution belongs to every American, and we need to keep it that way.
There is no moderate way to amend the Constitution to discriminate against a group of Americans.
Amending our Constitution would have a very real impact on real people's lives - people like Lydia Ramos in California.
Lydia's partner of 14 years died in a car accident, setting off a legal and emotional nightmare.
The coroner refused to turn Lydia's late partner's body over to her, and the daughter they raised together was taken away by her late partner's relatives after the funeral.
The two were kept apart for months - in a time where they most needed each other.
"Amending the federal Constitution would cement this discrimination and put thousands of mothers and daughters in the nightmare we faced," Lydia says.
The kind of amendment President Bush supports would put families all across America in jeopardy.
The president is supposed to be the leader of our entire nation, but he is turning his back on that duty by supporting an attempt at such extreme discrimination.
Young gay people listening to him will wonder if they can be part of the American dream when marrying the person they love might never be part of their future.
Straight or gay, this is deeply troubling for a lot of people, and we're going to stand with them and fight this attempt to silence and discriminate against our families.