Charles Bridges in The Christian Ministry writes:

Nor let it be thought, that studious habits must necessarily infringe upon our more active employments. What shall we say to the nine pondrous folios of Augustine, and the thirteen of Chrysostom - volumes not written, like Jerome’s, in monastic retirement, but in the midst of almost daily preaching engagements, and conflicting, anxious, and most responsible duties - volumes - not of light reading, the rapid flow of shallow declamation - but the results of deep and well-digested thinking? The folios also of Calvin - the most diligent preacher, and of Baxter, the most laborious pastor of his day - full of though and matter, bear the same testimony to the entire consistency of industrious study with devoted Ministerial diligence. The secret of this efficiency seem to have much consisted in a deep sense of the value of that most precious of all talents - time; and of an economical distribution of its minutest particles for specific purposes. Mr. Alleine would often say, “Give me a Christian, that counts his time more precious than gold.” [...] But here we should be, like the miser with his money - saving it with care, and spending it with caution. [...] And since goldsmiths and refiners’ [Boyle] remarks - “are wont all the year long to save the very sweepings of their shops, because they may contain in them some filings or dust of those richer metals, gold and silver; I see not, why a Christian may not be as careful, not to lose the fragments and lesser intervals of a thing incomparably more precious than any metal - time; especially when the improvement of them by our meletetics may not only redeem so many portions of our life, but turn them to pious uses, and particularly to the great advantage of devotion.”

A common question in Sabbatarian circles is whether or not believers should go out to eat on Sunday. The line of reasoning is that even though the believer may be observing the Sabbath, he or she is not letting the people who are serving him or her observe the Sabbath. Meredith Kline has an interesting paragraph on the subject in Kingdom Prologue, p. 81.

Whether the Sabbath is viewed as God’s promise of the consummation of the covenant order or as man’s pledge of devotion to the covenant suzerain, it is always a sign of the covenant. In this primal sign the covenant receives comprehensive expression, for the Sabbath brings out the nature of the covenant as both personal relationship and historical kingdom program. For Israel the Sabbath was the sign of the covenant par excellence (Exodus 31:16, 17). That the Sabbath was appointed to the covenant community at the creation suggests that it is of perpetual validity, as long at least as that community experiences life and history as a succession of days. However, if we appreciate this essential connection of the Sabbath with the covenant, and especially if we recognized that the Sabbath is always covenantal promise and privilege as well as duty, we will avoid thinking of it abstractly as at any time after the Fall a universal ordinance of general application to the world at large. The Sabbath belongs to the covenant community exclusively.

According to Kline, it seems that so long as the people serving you are not in the covenant, there should not be a concern. Presumably, if they were in the covenant, they would not be working on the Lord’s Day. However, it still may not be prudent to [even indirectly] encourage people in their anti-covenantal activities. This is a very sticky situation, for one could suggest a multitude of examples where we may be encouraging people in this direction.

Please feel free to add to this discussion with comments.