KJV:
But when they shall lead you, and deliver you up, take no thought beforehand what ye shall speak, neither do ye premeditate: but whatsoever shall be given you in that hour, that speak ye: for it is not ye that speak, but the Holy Ghost.
NASB:
"When they arrest you and hand you over, do not worry beforehand about what you are to say, but say whatever is given you in that hour; for it is not you who speak, but it is the Holy Spirit.