Based on a Naaleh.com shiur by Rabbi Beinish Ginsburg
The Chafetz Chaim writes that if you hire two workers and you only have enough money to pay one, you must pay the more impoverished worker first. This is hinted at in the Torah, which mentions the word ani (a poor person) in connection with the commandment of paying a worker on time.
If both workers are equally poor and one of them is a relative, the relative does not take precedence. If you don’t have enough money to pay both of them, you must split the money you do have between them. Then when you have the rest of the money, you can make it up to them.
If you hired a worker the day before and could not pay him on time and then you hired a second worker the next day and you now have a chance to pay him on time, which worker takes precedence? Jewish law dictates that one should pay the second one first to in order to avoid violating bal talin again.
You shouldn’t hire a worker if you know you won’t be able to pay him, unless the worker agrees to wait. If the minhag hamakom (custom) is that a worker gets paid on the pay day determined by the employer, then you can hire a worker and not pay him right away because it’s assumed that the worker has agreed to be paid later.
If you hire a worker and you know you will not be present on pay day, you should set aside money to pay him so the money’s there when the work is completed.
One who holds back the wages of a worker is considered as if he has killed him. The Alshich says that one must be very careful in this matter. If a worker who hasn’t been paid returns home to his hungry family and they cry out to Hashem, He will listen to them because He hears the prayers of those who suffer. Not only has the employer then violated bal talin and gezel (stealing) but also lifnei ivir (not placing a stumbling block), because he has caused Jews to pray to Hashem to hurt another Jew
The Arizal says that whoever fulfills the mitzvah of paying a worker on time receives great reward in this world too. This is in addition to the reward awaiting him in the world to come. This is hinted to in the verse, “B’yomo titen secharo.” On that day you shall pay his wages. The first letters are bet, taf, shin, which spell Shabbat. When a Jew keeps Shabbat he receives a neshama yeteira (an extra soul). This also occurs when a person pays his workers on time.
One should set the price before the work begins to avoid questions of gezel. It’s very common for a worker to argue over compensation. Even if he forgives you to avoid further argument, deep down he may not forgive you completely and there may be a question of dishonesty.
In the event a set price wasn’t established, the wage is calculated according to the norm. It is very hard to calculate exactly what that is, and if you pay your worker less it could be gezeila. If you want to avoid this, you’ll have to end up giving more. Therefore, one should always set the price first. A Torah scholarshould be extra careful to do this in order to avoid a chilul Hashem (profaning Hashem’s name).