King James Version
For both he that sanctifieth and they who are sanctified are all of one: for which cause he is not ashamed to call them brethren,English Standard Version
For he who sanctifies and those who are sanctified all have one origin. That is why he is not ashamed to call them brothers,New International Version
Both the one who makes men holy and those who are made holy are of the same family. So Jesus is not ashamed to call them brothers.