Mark 10:40

40 but to sit on my right hand or on [my] left hand is not mine to give; but [it is for them] for whom it hath been prepared.

Mark 10:40 In-Context

38 But Jesus said unto them, Ye know not what ye ask. Are ye able to drink the cup that I drink? or to be baptized with the baptism that I am baptized with?
39 And they said unto him, We are able. And Jesus said unto them, The cup that I drink ye shall drink; and with the baptism that I am baptized withal shall ye be baptized:
40 but to sit on my right hand or on [my] left hand is not mine to give; but [it is for them] for whom it hath been prepared.
41 And when the ten heard it, they began to be moved with indignation concerning James and John.
42 And Jesus called them to him, and saith unto them, Ye know that they who are accounted to rule over the Gentiles lord it over them; and their great ones exercise authority over them.
The American Standard Version is in the public domain.