All laws are based on SOMEONE taking moral authority, and defining other people's choices.
ALL LAWS.
It's only a matter of "who" is imposing that moral authority.
Atheists will talk all day about how "moral" they are... but as soon as you bring up the law, they will suddenly backstep, and suddenly pretend they don't have any particular morals. They will even act as if having morals is somehow "outdated" or "unevolved". But if you talk about injustice in the world, they'll suddenly have morals again, and talk all day about it.
So, when atheists act as if they have no particular moral beliefs, and they are NOT trying to impose their morals on others... it's all just nonsense.
In one breath they'll talk about how moral they are, and in the next breath they'll talk about how wrong it is to have morals or impose your morals on others, and in the next breath after that they'll tell you how laws should be changed to make things more "morally correct".
An atheist is just a walking sack of contradictions.
Does a couple being homosexual, and married, take away your ability to live your life within the moral boundaries you have promised God that you'll live within? Do a homosexual married couple going about their lives, make you unable to be faithful to your spouse?
Do they make you unable to worship no other gods but YHWH?
Do they make you unable to refrain from stealing?
Do they make you unable to refrain from murder?
Do they make you unable to honour your mother and father?
Do they make you unable to keep the Sabbath day?
Do they make you unable to refrain from lying?
Do they make you unable to refrain from covetousness?
Do they make you unable to refrain from taking God's name in vain?
Do they make you unable to refrain from having sex with another man?
Do they make you unable to refrain from bestiality?
Do they make you unable to stay faithful to your spouse?
Do they make you unable to refrain from incest?
Do they make you unable to refrain from consuming human blood?
Do they make you unable to refrain from eating meat and dairy?
Do they make you unable to utilize your right to preach?
Do they make you unable to open a church?
Do they make you unable to pray?
Do they make you unable to socialize with other Christians?
Do they make you unable to marry one woman?
Do they make you unable to refrain from sacrificing anything with yeast or honey?
Do they make you unable to refrain from eating pork?
I'm sure you get the point. There is nothing about two people being in a consensual gay marriage that stops you from being able to be a Christian, in any way whatsoever. The only way in which it places any limits on your behaviour, is when you try to force your Christian rules onto those people. As per the law, those people have a right to make their own choices about their own way of life, so long as it doesn't harm anybody else. And two people being gay, married, and living in a house, leading their lives,
does not harm you.
That's the kicker, really.