Shared ground
Hebrews 10:5–10 continues the argument that repeated sacrifices could not achieve what they were meant to point toward (10:1–4). The writer treats words from Scripture as what Christ says “when he comes into the world,” and uses them to contrast two things: ongoing sacrificial offerings and the doing of God’s will.
The passage is clear that God did not “desire” sacrifices as the final goal (vv. 5–6, 8), even though they were offered “according to the law” (v. 8). In their place, the text highlights a “prepared body” (v. 5) and a mission summarized as “I have come to do your will” (vv. 7, 9). The writer then states the result for “we”: sanctification is tied to “the offering of the body of Jesus Christ once for all” (v. 10).
Where interpretation differs
Who is speaking in the quoted Scripture (vv. 5–7). The writer frames the quotation as Christ speaking. Some readers take this straightforwardly: the preexistent Christ is speaking as he enters the world. Others think the writer is using the Psalm as a representative voice (the faithful person or the Messiah as anticipated in Scripture) and applying it to Christ, without implying Christ literally spoke these words at that moment.
What “a body you prepared for me” most emphasizes (v. 5). Many read it mainly as about incarnation: the Son truly takes on a human body so he can offer himself. Others agree incarnation is involved but think the stress is more on readiness for obedience and sacrifice—God “prepares” the servant for the mission summarized in v. 7.
What “the first” and “the second” refer to (v. 9). Some understand “the first” as the whole sacrificial system under the law and “the second” as doing God’s will accomplished through Christ’s self-offering. Others narrow it: “the first” is the category of animal sacrifices, and “the second” is Christ’s own offering (described in v. 10) as the new way God provides.
What “sanctified” means here (v. 10). Some take it mainly as a set-apart status granted through Christ’s offering (a decisive change in standing before God). Others include that but hear more: sanctification also implies a real moral cleansing and transformation that flows from the once-for-all offering, even if this verse highlights the decisive basis.
Why the disagreement exists
The passage moves quickly from quotation to conclusion, so readers must infer how literally to take the quotation’s framing (“when he comes… he says”), how broad “the first/the second” is, and how to relate v. 10’s “sanctified” to the letter’s wider language about cleansing, access, and perseverance (10:11–18; 10:19–22).
What this passage clearly contributes
Explicitly, Hebrews 10:5–10 claims that sacrifices commanded by the law were not God’s ultimate end, and that Christ’s coming is presented as oriented toward doing God’s will. The text connects that will to a prepared body and to Christ’s single self-offering. It also links the community’s sanctification to that once-for-all offering, setting up the next paragraph’s contrast between repeated priestly work and a completed act (10:11–18).