Q. The book of Hebrews says that Jesus is not ashamed to call his followers his brothers and sisters. To support this, it quotes from Psalm 22 (“I will declare your name to my brothers and sisters . . .”) and from Isaiah: “I will put my trust in him” and “Here am I, and the children God has given me.” I’ll grant that Psalm 22 is a Messianic psalm that Jesus applied to himself. But at that place in Isaiah, the prophet is clearly talking about himself. So it seems that the writer of Hebrews has quoted those Scriptures out of their original context, no?
Actually not. As I explain in my study guide to Deuteronomy and Hebrews, the authorof Hebrews follows “a Christological and typological method . . . in which statements from the First Testament that were originally made by, to, or about other figures are attributed to Christ.” The author sees Christ as culmination of the story of God’s covenant dealings with humanity, and so earlier figures, events, institutions, and objects are seen as prefiguring his life and work. But there is always a close and appropriate thematic connection between the earlier context in the First Testament and the situation in the life of Christ.
As I also explain in the guide, those two quotations from Isaiah come closely together “at the point where the prophet resolves to commit himself and his family to trusting in God in the face of hostility and an uncertain future. This attitude of trust is the same one Jesus had when he came to earth and faced similar hostility and uncertainty. And so the people he commits to God with himself are similarly his ‘children.’ Brothers, sisters, children—Jesus relates to all of us as a fellow member of the human family.” The author of Hebrews can appropriately draw this connection.
Finally, because we are used to quoting “Bible verses” a little differently today, it’s important to recognize that while the author of Hebrews often quotes only brief phrases from First Testament passages, this is done to appeal to the entire context in which they appear. The assumption is that the audience will be familiar with these larger contexts and consider the argument in light of them. These are not “proof texts,” but more like “arrows” pointing to broader passages.
I hope this information is helpful in addressing your concerns.