Mark 14:10-12

10Then Judas Iscariot, who was one of the twelve [disciples], went to the chief priests to betray Jesus to them.

11When they heard this they were delighted, and promised to give him money. And he began looking for an opportune time to betray Jesus.

12On the first day [of the festival] of Unleavened Bread, when [as was customary] they sacrificed the Passover lamb, His disciples asked Him, “Where do You want us to go and prepare for You to eat the Passover?”