Personal preference is always the RSV:
9 But we see Jesus, who for a little while was made lower than the angels, crowned with glory and honor because of the suffering of death, so that by the grace of God he might taste death for every one. 10 For it was fitting that he, for whom and by whom all things exist, in bringing many sons to glory, should make the pioneer of their salvation perfect through suffering. 11 For he who sanctifies and those who are sanctified have all one origin. That is why he is not ashamed to call them brethren, 12 saying, "I will proclaim thy name to my brethren, in the midst of the congregation I will praise thee."
Verse 9 (and, indeed, the verses which precede it) speaks of the incarnation. Contextually, that necessarily implies that the origin needs be that self-same act. To me, this passage speaks of how Christ came down and became man, dwelt among us, and through that life entered death that he might raise us from glory into glory. And it is meet and just that Christ is this truth.
It is the humanity of Christ which makes it so that the savior might elevate us. It is his life and death as a man which makes it so that we might be considered "brothers", and "sons". It is the flesh and blood of Christ which makes it possible for God to consider human beings as "brethren".