KJV:
Now we command you, brethren, in the name of our Lord Jesus Christ, that ye withdraw yourselves from every brother that walketh disorderly, and not after the tradition which he received of us.
NASB:
Now we command you, brethren, in the name of our Lord Jesus Christ, that you keep away from every brother who leads an unruly life and not according to the tradition which you received from us.