'First Day' in the Bible

On the first day of unleavened bread, when the paschal lamb is kill'd, his disciples said to him, where would you have us go and prepare for your eating the paschal lamb?

went to the sepulchre very early in the morning, the first day of the week, at sun-rising.

Now Jesus being risen early on the first day of the week, he appear'd first to Mary Magdalene, whom he had dispossess'd of seven demons.