Mark 10:40 in the King James Version
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.
Context
39 They said to him, “We are able.” Jesus said to them, “You shall indeed drink the cup that I drink, and you shall be baptized with the baptism that I am baptized with;
40 but to sit at my right hand and at my left hand is not mine to give, but for whom it has been prepared.”
41 When the ten heard it, they began to be indignant toward James and John.