If you can't make secular decisions in your job representing all people in your constituency, if you can't separate your religious belief and personal morals from what is legislatively appropriate, then just maybe, you shouldn't be a politician. On the other hand, if you can act appropriately as a legislator, then I have no problem with a person who is personally deeply religious from holding elected office.
If you are a Senator or Representative in the US, you also represent the atheists in your constituency, as well of those of all other religious beliefs than your own. You don't just represent the ones who align with your religious belief.
So yeah, this is exactly what I was talking about: this is disenfranchising people based on their religion.
> If you can't make secular decisions in your job representing all people in your constituency, if you can't separate your religious belief and personal morals from what is legislatively appropriate, then just maybe, you shouldn't be a politician. (...) If you are a Senator or Representative in the US, you also represent the atheists in your constituency, as well of those of all other religious beliefs than your own. You don't just represent the ones who align with your religious belief.
This is just an isolated demand of rigor, it's a standard that you would not apply in other circumstance. Try making the same argument, but replacing religion with political party. "Sure, you are personally deeply aligned with Democratic policy, but you also represent Republicans in your constituency, so you should separate your personal beliefs and morals from your politics, and don't push for policy that your Republican constituents would not agree with". This is of course ridiculous.
You need to understand that what you proposing here is plainly disadvantaging (some) religious beliefs compared to other philosophies, and holding them to a different, higher standards. Why do majority of voters have to give "sufficient secular reason" for a given law? Constitution doesn't demand this sort of "parallel construction".
If Christians want to fight climate change because they believe that's what God wants, great! They should seek policies to do just that. But what the lawmakers cannot do is write laws that say "the EPA must impose greenhouse gas limits because God commands it."
The lawmakers can have their reasons for the bills they write (they can believe it's what God wants, or they can know it's what their voters believe it's what God wants), but the laws themselves cannot be based on religion.