The Uyaqara (Leviticus) Laws state such.

Barashyth (Genesis) 1:5 says, “The evening and the morning were the first day.” A day began when the preceding day closed, at sunset. The dark part of the day came first, then the light part.

In describing how to honor one of the feast days, YAHUAH instructed the YasharALyts (erroneously called “Israelites” The Native Born), “From evening to evening, you shall celebrate your Shabath” (Uyaqara (Leviticus) 23:32). “Evening” is when the sun becomes even with the horizon, what we call sunset. “In the evening, at the going down of the sun ...” (Dabarym (Deuteronomy) 16:6). “That evening, after sunset …” (Marqus (Mark) 1:32).

When the YasharALyts returned to Yarushalam (erroneously called “Jerusalem”) after the Babylonian captivity, NachamYah (Nehemiah) had to teach them how to observe the Shabath. To prevent the YasharALyts from carrying on their usual day-to-day business on Shabath, NachamYah (Nehemiah) commanded that the gates of Yarushalam be shut “when the evening shadows fell on the gates of Yarushalam before the Shabath” (NachamYah (Nehemiah) 13:15-19).

When the sun goes down on Friday evening, Shabath begins. It is this creation memorial that we are to remember and keep Yum HaQadash (The Set Apart Day) (Shamuth (Exodus) 20:8).