My religious tradition (reformed evangelical christian) takes the sabbath pretty seriously, as stated in the Westminster Confession of Faith:
> VIII. This Sabbath is to be kept holy unto the Lord when men, after a due preparing of their hearts, and ordering of their common affairs beforehand, do not only observe an holy rest all the day from their own works, words, and thoughts about their worldly employments and recreations, but also are taken up the whole time in the public and private exercises of his worship, and in the duties of necessity and mercy.
Notice the last statement makes an allowance for acts of mercy and duties of necessity, which would certainly include things like being a Doctor or a Policeman, but I've always considered my duties as a Software Engineer being on-call to be borderline on whether or not they meet that standard. Certainly my employer(s) have thought they were necessary... But who are we kidding. Most of this stuff isn't life or death and waiting till Monday to get it fixed probably wouldn't be that big of a deal.
(I should probably mention that although these are the standards of the Church I attend they're rarely enforced in any meaningful sense - being treated more as a matter of personal conscience than of discipline... and particularly when it comes to the Sabbath)
Still I wrestle with it... not having a firm enough conviction to quit a job where I've had to do it, though if it were an every week thing, particularly if I had to regularly miss the Sunday service, I almost certainly would.
If I could make one plea, it would be for tolerance and compromise. I realize religious beliefs can be pretty weird in this day and age, but they're often sincerely held, and there's usually a solution available if the company is willing to consider it. (for example I'm just fine being on-call any other day of the week, and a surprising oddity of the reformed tradition, we don't really have religious holidays: https://heidelblog.net/2017/03/the-westminster-divines-on-ho...)