Can my company fire me if I apply for a job with my same company?

There is a position open with my company that I will really like, they told me that it be not the right time for me to get due to the fact that they did not have anybody to work my position however my representative had promised that position to me if it became available. I saw what I believe to be the position online posted but with confidential employer. Can I apply for it? What if itis indeed the position? Could they fire for applying online or looking for a commission. Please help.

Thanks
They would not have a case to fire you. If it was a biddable company they would help you get it and just ask you to do a dual role position until your position can be full up. legally they cannot fire you unless you have signed a contract to say you wont apply for a different position in the company.
they should be happy to have an employee next to some drive and ambition!
I don't see how they can fire you. If they want you to stick with your position, they just won't choose you for the strange position. i dont see why they would. In my past, when i was a department head it be my job as a department head to train the people below me, if a promotion came up, i would have a better shot at it if i had someone available to lift my spot.
No if they promissed it too you yull probably get it as soon as they get a replace for you.
Keep buggin them companys SUCK if ya ask me!!!!!!!!!!!!! You are probably employed 'AT WILL'
theirs, they could fire you for doing something and claim it be for some other reason entirely.

Dont look for another job while you are at work thats an OFFICIAL way to find fired.
I think you're pretty bold for doing this...

Why were you fired?

I'd give it a try... what's the worst that could appear... ?

you get fired again?

The best is that you could redeem yourself
I would say no. Most companies encourage their workers to apply to internal postings. It shows that the employees are interested in improving themselves and are feeling like to become more of an asset to the company. The problem here is, the posting wasn't necessarily "internal". If it was and you're interviewed, you're going to be asked why you want that position. Your answer better be the best one!!!
I don't give attention to the company would fire you if you are a good employee. If you are certain to be precise the position you were promised, why don't you talk to your manager around it and explain the situation. If you don't look after yourself, then you might skip the opportunity. I would suggest to have a talk beside your manager that promised that position to you.

Good luck.
I would suggest you inquire with your boss if this is the job. Seems they would be skirting the regular procedure of "hiring from within" which would probably upset most employees. If they were to be fair, they should be hiring to replace you so you could own the position you were promised. It depends on the company, but they could be offended if they found out it was you that be applying for the job since it would seem that you're looking elsewhere (If that is impossible to tell apart company you are working for). I would suggest to ask who this "confidential employer" with the help of a friend (like if there is a contact info within the online profile, use your friend to ask that question. That way, the likeliness for them to find out it was you that be searching for the job is minimum and it doesn't hurt to ask). You can also ask those within your own company if they post these job online, to get a better idea. Hopefully that helps, Good Luck!