Mark 10:38-40

But Jesus said unto them, Ye know not what ye ask: can ye drink of the cup that I drink of? and be baptized with the baptism that I am baptized with? And they said unto him, We can. And Jesus said unto them, Ye shall indeed drink of the cup that I drink of; and with the baptism that I am baptized withal shall ye be baptized: but to sit on my right hand and on my left hand is not mine to give; but it shall be given to them for whom it is prepared.