Hebrews 2:11

For both he that sanctifieth and they that are sanctified are all of one; for which cause he is not ashamed to call them brethren.

This is a further explanation of the fitness of Christ's death for people. Since the Son has taken upon him the form of human beings, and in that sense is one with them, he is not ashamed to call them brethren, even to the extent of partaking of all their sorrows and sufferings, even death itself. The sanctification spoken of here is on a higher level than is usually thought of in connection with this term. It applies to the setting up of a new relationship to God rather than to achieving some greater holiness of character and partakes of the meaning of "justification" as used by Paul in Romans and elsewhere. Adam Clarke, speaking of "sanctifieth" in this verse, wrote:

The word does not merely signify one who sanctifies or makes holy, but one who makes atonement or reconciliation to God; and answers to the Hebrew word [~kaphar], to expiate (Exodus 29:33-36). He that sanctifies is he that makes the atonement; and they who are sanctified are they who received the atonement, and, being reconciled unto God, become his children, through adoption, by grace.[16]

That Christ is "not ashamed to call them brethren" is a most instructive thought. That the sinless and perfect Saviour should not be ashamed of vile and sinful man, and through his great love for them, should consent to partake of all their sufferings, even death, and should even go so far as to receive them as his spiritual body and make of them his bride - that must be hailed as an attitude of loving grace that beggars all description. Nor will Christ ever be ashamed of his brethren but will confess them before God and his holy angels (Mark 8:38). But if the attitude of Christ toward people is so commendable beyond all human comprehension, how loathsome is the opposite attitude of people who are ashamed of him?