Is it permitted to dimiss an older yid from cleaning a shul because he is too slow and expensive, and replace him with a goy? He has been working here for about 8 years. Thank you.
The answer to this question depends on the circumstances. There is no prohibition on dismissing workers, if there is a need for this. However, if the loss is not significant, it is forbidden to employ a non-Jew in place of a Jew. If the loss is significant (for instance, a 20% difference would certainly be considered significant; because payment for the cleaner is taken from public money, a smaller sum might also be sufficient), it is permitted to do so. If possible, one must seek to employ another yid in place of the former employee.
Sources: Shut Rema, no. 10, cited lehalachah in Ahavas Chesed.