Mark 15:42-43
(42) And now when the even was come, because it was the preparation, that is, the day before the sabbath,
(43) Joseph of Arimathaea, an honourable counsellor, which also waited for the kingdom of God, came, and went in boldly unto Pilate, and craved the body of Jesus.
Preparation day was the day before the sabbath, that is the day when Jesus died, Friday the 6th day