Mark 14:17

14 and wherever he enters in, tell the master of the house, `The Teacher says, "Where is the guest room, where I may eat the Passover with my disciples?"`

15 He will himself show you a large upper room furnished and ready. Make ready for us there."

16 His disciples went out, and came into the city, and found things as he had said to them, and they prepared the Passover.

17 When it was evening he came with the twelve.

18 As they sat and were eating, Jesus said, "Most assuredly I tell you, one of you will betray me -- he who eats with me."

19 They began to be sorrowful, and to ask him one by one, "Surely not I?" And another said, "Surely not I?"

20 He answered them, "It is one of the twelve, he who dips with me in the dish.