It shall be unto you a sabbath of rest, and you shall humble yourselves: in the ninth day of the month at evening, from evening unto evening, shall you celebrate your sabbath.
Read Chapter 23
George Leo Haydock
Sabbaths. The Church adopts this custom in her divine office. The Jewish day began and ended with sun-set, Exodus xii. 6. (Calmet)
No part of the ninth of Tisri belonged to this feast, (ver. 27,) which only began at the expiration of it. (Haydock)