K’doshim says, “Keep my Sabbaths and respect My sanctuary” (Lev. 19:30). Targum Onkelos adds two words for the sake of greater clarity: “Keep My Sabbath days” (which shows, says Sforno, that the phrase includes festivals) and “respect My sacred House” (which Rashi and others say includes all the Temple precincts).
Both innovations are important: the festivals must be observed with Sabbath-like dedication, and not only in the Temple itself but in its surrounds people must behave reverently.
Another possibility is that the original verse is an example of Biblical parallelism in which the two halves of the passage say the same thing in different words, and thus “respect My sanctuary” refers to the Sabbath. Shabbat is the epitome of holiness. Being holy people, which is what the Torah commands at the beginning of K’doshim, means investing time’s peaks with sacredness.
The other verses in the portion speak of ethical relationships, further illustrating the concept of holiness. Being holy means attaching sanctity to every place, every moment, every thought and every situation.