The penal law of the Sabbath. Exodus 35:2-3. In the fourth commandment the injunction to observe the seventh day is addressed to the conscience of the people (see Exodus 20:8 note): in this place, the object is to declare an infraction of the commandment to be a capital offence. The two passages stand in a relation to each other similar to that between Leviticus. 18, Leviticus. 19, and Leviticus. 20. It seems likely that the penal edict was especially introduced as a caution in reference to the construction of the tabernacle, lest the people, in their zeal to carry on the work, should be tempted to break the divine law for the observance of the day.

And the Lord spake unto Moses,.... After he had described to him the place of worship, and appointed the priests that should minister in it, and ordered the making of all things appertaining to it, and the workmen that should be concerned therein, he repeats the law of the sabbath, and puts in mind of the time of worship:
saying: as follows.

Orders were now given that a tabernacle should be set up for the service of God. But they must not think that the nature of the work, and the haste that was required, would justify them in working at it on sabbath days. The Hebrew word shabath signifies rest, or ceasing from labour. The thing signified by the sabbath is that rest in glory which remains for the people of God; therefore the moral obligation of the sabbath must continue, till time is swallowed up in eternity.

Verily my sabbaths ye shall keep--The reason for the fresh inculcation of the fourth commandment at this particular period was, that the great ardor and eagerness, with which all classes betook themselves to the construction of the tabernacle, exposed them to the temptation of encroaching on the sanctity of the appointed day of rest. They might suppose that the erection of the tabernacle was a sacred work, and that it would be a high merit, an acceptable tribute, to prosecute the undertaking without the interruption of a day's repose; and therefore the caution here given, at the commencement of the undertaking, was a seasonable admonition.

(cf. Exodus 35:2-3). God concludes by enforcing the observance of His Sabbaths in the most solemn manner, repeating the threat of death and extermination in the case of every transgressor. The repetition and further development of this command, which was included already in the decalogue, is quite in its proper place here, inasmuch as the thought might easily have occurred, that it was allowable to omit the keeping of the Sabbath, when the execution of so great a work in honour of Jehovah had been commanded. "My Sabbaths:" by these we are to understand the weekly Sabbaths, not the other sabbatical festivals, since the words which follow apply to the weekly Sabbath alone. This was "a sign between Jehovah and Israel for all generations, to know (i.e., by which Israel might learn) that it was Jehovah who sanctified them," viz., by the sabbatical rest (see at Exodus 20:11). It was therefore a holy thing for Israel (Exodus 31:14), the desecration of which would be followed by the punishment of death, as a breach of the covenant. The kernel of the Sabbath commandment is repeated in Exodus 31:15; the seventh day of the week, however, is not simply designated a "Sabbath," but שׁבּתון שׁבּת "a high Sabbath" (the repetition of the same word, or of an abstract form of the concrete noun, denoting the superlative; see Ges. 113, 2), and "holy to Jehovah" (see at Exodus 16:23). For this reason Israel was to keep it in all future generations, i.e., to observe it as an eternal covenant (Exodus 31:16), as in the case of circumcision, since it was to be a sign for ever between Jehovah and the children of Israel (Ezekiel 20:20). The eternal duration of this sign was involved in the signification of the sabbatical rest, which is pointed out in Exodus 20:11, and reaches forward into eternity.