Great and Holy Saturday is the day on which Christ reposed in the tomb. The Church calls this day the Blessed Sabbath.
“The great Moses mystically foreshadowed this day when he said:
God blessed the seventh day.
This is the blessed Sabbath
This is the day of rest,
on which the only-begotten Son of God rested from all His works….”
to continue reading, click: https://www.oca.org/saints/lives/2022/04/23/26-great-and-holy-saturday
The icon depicts the Descent into Hades.