However, since you did not specify what context you meant, I would consider "cycled" to mean all water parameters are within normal parameters (ie, ammonia-0, nitrites-0, and nitrates-under 50ppm (for a FO system)).
I wouldn't add cured live rock from an lfs to your display. There will be some die off, and who knows how long they have really had it. It is pretty easy to cure it yourself, and after your done you can put it right in with no worry.