'Cup' in the Bible

Whoever gives you a cup of water, because you are Christ's, truly I say to you, he will in no way be without his reward.

But Jesus said to them, You have no knowledge of what you are saying. Are you able to take of my cup? or to undergo the baptism which I am to undergo?

And they said to him, We are able. And Jesus said to them, You will take of the cup from which I take; and the baptism which I am about to undergo you will undergo:

And he took a cup, and when he had given praise, he gave it to them: and they all had a drink from it.

And he said, Abba, Father, all things are possible to you; take away this cup from me: but even so let not my pleasure, but yours be done.