Having issued a La'av against working on Yom Kipur in Pasuk 28, why does the Torah repeat it here?
Rashi #1: To add a second La'av. 1
Rashi #2: To include the night of Yom Kipur in the Isur. 2
Uoma, 81a: The Torah presents five Pesukim with regard to the prohibition against Melachah on Yom Kipur - See Torah Temmah, note 95 - One, a warning against performing Melachah in the day and one ... in the night (See Torah Temimah, note 96); one, the punishment for performing Melachah in the day, and one ... in the night, and one to learn a Gezeirah Shavah from Melachah on to Inuy.
See Sifsei Chachamim.
?Kol Melachah Lo Sa?asu?. What is the significance of the five times that the Torah inserts the Isur Melachah ? in Pesukim 28, 30 and 31, 16:29 and Bamidbar 29:7?
Yoma, 81a: 1 & 2. A warning against performing Melachah in the day and in the night 1 ; 3 & 4. the punishment for performing Melachah in the day and in the night, >5. To earn a Gezeirah Shavah from Melachah on to Inuy both in the day and in the night.
See Torah Temimah, note 96.
What are the implications of "be'Chol Moshvoseichem"?


