The Parasha, and Haftorah from Ezekiel, both list the ways a Cohen could live and be holy. Holiness was maintained by, for example, avoiding contact with deceased apart from very close relatives, not marrying a widow or divorcee, not shaving, and not drinking alcohol.
Duties of holiness were at one level for the ordinary Israelite, at a higher level for the Levite, a still higher level for a Cohen, and the highest level for the Cohen Gadol. R’ Eli Munk wrote that this progression in holiness also occurs in time from the ordinary week day to Shabbat, through to Yom Kippur.
The more Mitzvot of Shabbat that we keep, the greater is our experience of its holiness. From lighting the Shabbat candles, to the Brachot for the wine and the challa, to the Shabbat meals, benching, not working, going to Shule, hearing the Torah being read, saying the prayers, and ending the day making Havdala; the more we observe, the greater our appreciation of the day.