I work for a large corporation and have been told on several occassions that I am a wonderful employee and that they would love to make me a manager if my schedule would open up. The only thing in my schedule in my Sabbath keeping, which means I do not work from Friday 6pm until Saturday 6pm, and its for obvious religious reasons. I am a member of an established denomination that keeps this time of rest, so I'm not just making it up because I don't want to work at that time. When I was hired I stated my inability to work on the Sabbath and have never gone back on this, no matter how many times they asked me to reconsider. Is this religious descrimination?

It depends. If the position you want to transfer to is one that requires work on theose days, it may not be reasonable for your employer to exempt you from it. Without knowing what the business is and what is required for the position, it is impossible ot say whether it is reasonable or not.

I realized yesterday that I forgot to put that it was a retail job. Most managers get one of the two weekend days off but thats probably just a nice thing that they do for each other not neccessarily a rule. When I was looking into this on my own I noticed something that said they didn't have to hire you if it "caused undo hardship for the company" and I wondered if they might throw this in there under that...

It is possible that it would be an undue hardship. It really depends. If there are two of you and you always need Friday night and Saturday off, it could be quite a burden to the other manager to always have to work those days, which are among the least desireable to work. Sometimes these things work themselves out like if the other manager always needs Sundays off for religious reasons, but that is rare.

Now if there are 20 managers who all rotate, it might not be burdensome at all to exempt you from having to work the Saturday shift once every 20 weeks.

When I worked retail this came up for me as well. The problem was that company policy required all managers to be in the store Saturday morning because that was the close of the business week and the highest volume sales. I was able to make an arrangement with the regional manager to for another manager to work Saturday morning if I always came in Saturday night, so it worked out okay in my case. Technically they were not required to make this accomodation however, as long as the reason for the rule was a clearly stated business purpose, and not to keep a certain kind of person from holding the management position.

Janet

Janet, that's an excellent explanation; thank you.

This is from EEOC's website:
Employers must reasonably accommodate employees' sincerely held religious practices unless doing so would impose an undue hardship on the employer. A reasonable religious accommodation is any adjustment to the work environment that will allow the employee to practice his religion. An employer might accommodate an employee's religious beliefs or practices by allowing: flexible scheduling, voluntary substitutions or swaps, job reassignments and lateral transfers, modification of grooming requirements and other workplace practices, policies and/or procedures.

An employer is not required to accommodate an employee's religious beliefs and practices if doing so would impose an undue hardship on the employers' legitimate business interests. An employer can show undue hardship if accommodating an employee's religious practices requires more than ordinary administrative costs, diminishes efficiency in other jobs, infringes on other employees' job rights or benefits, impairs workplace safety, causes co-workers to carry the accommodated employee's share of potentially hazardous or burdensome work, or if the proposed accommodation conflicts with another law or regulation.
http://www.eeoc.gov/types/religion.html

Your employer should be able to explain to you why promoting you into management with an accommodation for your religious belief would be an undue hardship.