Rabbi Chaim Vital gives us an anecdotal illustration of the lengths the Arizal went to in order to deal with his employees properly.

My teacher [the Arizal] was extremely careful regarding the commandment of paying a worker [on time]. He sometimes put off praying Mincha until he had paid [his workers]. This sometimes meant waiting to pray until sunset if he did not have the cash to pay the wages and had to send people all over to ask others for money until he had enough to pay the wages. Only then would he pray Mincha, saying, "How can I pray to G‑d when such a great mitzvah comes my way? Can I put it off and still face G‑d in prayer?"

"The wages of a hired worker shall not abide with you [through the night] until morning." (Lev. 19:13)

In another verse [that details this commandment] it is written: "On the day he [earns them] you shall give [him] his wages." (Deut. 24:15)

The full verse is: "Do not withhold the wages due to your poor or destitute hired hand, whether he is one of your brethren, or a proselyte living in a settlement in your land. You must give him his wage on the day it is due, and not let the sun set with him waiting for it. Since he is a poor man, and to you he lifts his soul, do not let him call out to G‑d, causing you to have a sin."

Jewish law clarifies:

What is "on time"? If the workman had finished the work during the day, he should be paid before the end of that day; if he finishes his work in the evening, he should be paid during the night. Whenever a person performs any commandment…he accrues an additional level of Shabbat holiness - even on the weekday… So also is the case with the workman hired by the week, or month, or year, if he has finished his work during the day, he should be paid during the day; if he has finished his work during the night, he should be paid during the night, but not later.

The employer does not transgress the law unless the workman demands his wages and he, the employer, has the money to pay. If the workman failed to demand his wages, or the employer lacks the money to pay the workman, then there is no violation of the law. Nevertheless, a scrupulous employer should, if necessary, borrow the money to pay the wages at the proper time, for the workman is poor and sets his heart upon his pay…"1

The initials of these words [in the above verse, "beyomo titein secharo"] spell Shabbat. This is because whenever a person performs any commandment or learns a lot of Torah on a weekday, he accrues an additional level of Shabbat holiness — even on the weekday. This applies to the [full] extent individuals are capable of accruing additional measures of Shabbat holiness.

Learning Torah and performing mitzvot increases the individual's divine consciousness. Since Shabbat is the day of higher divine consciousness, we may conceive of the additional measure of divine consciousness attained by learning Torah and doing mitzvot as a "piece of Shabbat" that is added the individual. This happens, of course, even in the case of divine service performed on weekdays.

This accords with what Rebbe Shimon bar Yochai taught, namely, that Torah scholars possess on weekdays the [level of] soul that the unlearned possess on the Shabbat.

Thus, the reward that G‑d grants Torah scholars for their studies, or to those who observe the commandments, is likened to that of a worker who expects his wages. For such people earn their [spiritual] desserts daily - even on weekdays, when they accrue additional measures of Shabbat holiness. Therefore, the initials of these words allude to the Shabbat.

Furthermore, the wages mentioned in this verse can understood, as well, to refer to the reward one earns each day [for his study and/or observance of the Torah]. These combine with the other [reward], the additional measure of Shabbat holiness that comes automatically with the Shabbat, as is known.

On Shabbat, every Jew's consciousness ascends a spiritual notch, no matter what.

Thus, these two additional measures [of divine consciousness] are given to the person on Shabbat. In this sense, [both types of] "wages" paid to this type of "worker" are paid on the Shabbat. The Shabbat is therefore alluded to in this verse, and this is the mystical meaning of "he who toils on the day[s] before the Shabbat will eat on the Shabbat."(Avoda Zara 3a) The employer is given an extra level of soul with which to sustain his soul…

The physical sense of this statement is simply that if one prepares his meals and other needs before Shabbat, he will be able to enjoy them on Shabbat, but if not, he will have nothing to enjoy because the preparations he should have done beforehand are forbidden to do on Shabbat. The spiritual sense of the statement is that the extent of one's spiritual experience or level of consciousness on Shabbat is proportional to the amount of spiritual preparation for Shabbat one engages in during the preceding week. In more prosaic terms: one cannot expect to live (think, eat) like an animal during the week and suddenly turn into an angel on Shabbat; if a person doesn't want to be left out of the action on Shabbat, he'd better put some time into refining himself while he still can - during the week.

Additionally, [this verse implies] that specifically someone who fulfills the commandment of paying a worker [on time] acquires the ability to attain an additional level of soul the following Shabbat. This reward is given to him measure for measure, for with regard to paying a worker [on time] it is said, "for… he lifts up his soul to you."(Deut. 24:15) Therefore, in recompense [for granting him his soul, so to speak], likewise the employer is given an extra level of soul with which to sustain his [weekday] soul [on the Shabbat]. And therefore, the Shabbat is alluded to in the initials of this verse.

The idiomatic meaning of "he lifts up his soul" is "he looks expectantly" or "he directs his desire."

[Adapted by Moshe-Yaakov Wisnefsky from The Writings of the Ari, Ta'amei HaMitzvot.]