He refers to the purification of sins later discussed in Hebrews chapters 9 and 10, which is the purification of all believers' sins.
As to whose sins is being cleansed, that is only a grammatical issue in this verse if one rejects the majority text reading. That reading makes it clear that the sins being purged are those of others than Christ, which information is obscured by minority readings dropping off ἡμῶν, though some minority readings have it in a different order* (note there are a few variations found in the bolded section, but here are the main two readings now):
MT: ὃς ὢν ἀπαύγασμα τῆς δόξης καὶ χαρακτὴρ τῆς ὑποστάσεως αὐτοῦ, φέρων τε τὰ πάντα τῷ ῥήματι τῆς δυνάμεως αὐτοῦ, διʼ ἑαυτοῦ καθαρισμὸν ποιησάμενος τῶν ἁμαρτιῶν ἡμῶν, ἐκάθισεν ἐν δεξιᾷ τῆς μεγαλωσύνης ἐν ὑψηλοῖς
NKJV trans. of bolded section: when He had by Himself purged our sins
NA28: ὃς ὢν ἀπαύγασμα τῆς δόξης καὶ χαρακτὴρ τῆς ὑποστάσεως αὐτοῦ, φέρων τε τὰ πάντα τῷ ῥήματι τῆς δυνάμεως αὐτοῦ, καθαρισμὸν τῶν ἁμαρτιῶν ποιησάμενος ἐκάθισεν ἐν δεξιᾷ τῆς μεγαλωσύνης ἐν ὑψηλοῖς,
ESV trans. of bolded section: After making purification for sins
* Per apparatus to NA28, a few minority texts have the ημων in this order:
των αμαρτιων ημων ποιησαμενος ℵ2 D1 H 33. 2464
DISCLAIMER: I hold to majority reading as reflective of the original reading.
Even if one goes with the NA28 reading, is purging sin from Christ reflective of what the book of Hebrews teaches? No. And that ties to the initial question, for the purging is clarified in chapters 9 and 10, where it is clear that believers are the ones being purified.
The first verses of Hebrews are summarizing what the author expands upon as major themes or at least clarifies or utilizes later in the book's text. Note from just v.3 (similar points could be made from v.2 and 4 also), using the ESV reading:
He is the radiance of the glory of God and the exact imprint of his
nature, [his position of glory is discussed in ch. 2 and 3:1-6]
and he upholds the universe by the word of his power [cf. 11:3]
After making purification for sins, [chapters 9 & 10, note also where the sitting down is noted in the larger text, per the next...]
he sat down at the right hand of the Majesty on high [10:12, 12:2]
Heb 1:3 refers to καθαρισμὸν ποιησάμενος τῶν ἁμαρτιῶν, and two factors relate to determining the purification—the middle voice participle ποιησάμενος (i.e. in what way He reflexively is associated with the cleansing of sin) and the theme brought by καθαρισμὸν itself. The latter, I believe, is more critical, so I will start there, but both have significance.
The Theme of Purification in Chapters 9 & 10
The word καθαρισμὸν is a noun for "cleansing" or "purification," but it derives from the verb καθαρίζω, "to make clean, to cleanse, to purify." This verb shows up a number of times in the key chapters of 9 and 10, as well as some other cognate words (I'll stick with ESV, though I tend to prefer NKJV since it follows better the majority text):
Heb 9:12-13 He entered once for all into the holy places, not by means of the blood of goats and calves but by means of his own blood, thus securing an eternal redemption. 13 For if the blood of goats and bulls, and the sprinkling of defiled persons with the ashes of a heifer, sanctify for the purification [καθαρότης] of the flesh
The ESV has "by means of his own blood," the NKJV "with his own blood" to express the "διὰ δὲ τοῦ ἰδίου αἵματος" of the Greek. The circumstantial idea expressed by the NKJV (see BDAG, A.3.c for that use of διὰ with the genitive) is better, in my opinion, as both the OT context and the NT context here in Hebrews supports that the blood was what the priest possessed to apply to the altar for the purpose of bringing about cleansing of the flesh of those the priest was offering for. While an argument can be made that nearly all the sacrifices had an atonement aspect, two particularly relate to Hebrews 9:12-14:
Neither of these sacrifices are referring to the cleansing of the priest (the OT priest needed [that is a key point] and had his own sacrifice to cleanse from his sin [Lev 16:6, 11-14] which was separate from and in preparation for the sacrifice for the people [Lev 16:15-28]). Rather, the day of atonement sacrifice and the red heifer sacrifice were done to God for those others the priest is ministering on behalf of.
But this cleansing of the flesh these sacrifices made are not what Christ's sacrifice did (so no, it is not referring to the Numbers 19:17 directly), for there is a greater work of cleansing done:
Heb 9:14 how much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify [καθαρίζω] our conscience from dead works to serve the living God.
Now v.14 does not mention sin, so what is the relation to Heb 1:3? That comes from the preceding point about blood bringing redemption (9:12), which is related to sin (Heb 2:14-18) in ways similar to the day of atonement sacrifice that cleansed sin. It is also found explicitly discussed in the following discussion of blood and forgiveness of sin:
Heb 9:22-23 Indeed, under the law almost everything is purified [καθαρίζω] with blood, and without the shedding of blood there is no forgiveness of sins. Thus it was necessary for the copies of the heavenly things to be purified [καθαρίζω] with these rites, but the heavenly things themselves with better sacrifices than these.
So "the heavenly things" need something better to be purified by, i.e. per v.14, the blood of Christ, and the context specifically is that one of the heavenly things is the forgiveness of sins.
Heb 9:27-28 27 And just as it is appointed for man to die once, and after that comes judgment, 28 so Christ, having been offered once to bear the sins of many, will appear a second time, not to deal with sin but to save those who are eagerly waiting for him.
Christ's blood sacrifice is what deals with the sin, including the cleansing from that. He came because the animal blood sacrifices were insufficent to cleanse it:
Heb 10:1-4 For since the law has but a shadow of the good things to come instead of the true form of these realities, it can never, by the same sacrifices that are continually offered every year, make perfect those who draw near. 2 Otherwise, would they not have ceased to be offered, since the worshipers, having once been cleansed [καθαρίζω], would no longer have any consciousness of sins? 3 But in these sacrifices there is a reminder of sins every year. 4 For it is impossible for the blood of bulls and goats to take away sins.
Notice how the author has described the animal sacrifices as not being able "to take away sins" (i.e., a total, permanent cleansing) to the point of completion ("make perfect"). This cleansing is linked to the sanctification of the believer:
Heb 10:10-14 And by that will we have been sanctified through the offering of the body of Jesus Christ once for all. 11 And every priest stands daily at his service, offering repeatedly the same sacrifices, which can never take away sins. 12 But when Christ had offered for all time a single sacrifice for sins, he sat down at the right hand of God, 13 waiting from that time until his enemies should be made a footstool for his feet. 14 For by a single offering he has perfected for all time those who are being sanctified.
The result being:
Heb 10:19-22 19 Therefore, brethren, having boldness to enter the Holiest by the blood of Jesus, 20 by a new and living way which He consecrated for us, through the veil, that is, His flesh, 21 and having a High Priest over the house of God, 22 let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience [by His blood, 9:14] and our bodies washed with pure [καθαρός] water.
So the purification Christ brings is discussed in chapters 9 & 10, and it is a purification of believers.
The Middle Voice Implications
According to Daniel Wallace in Greek Grammar Beyond the Basics (Zondervan Publishing House, 1996), the middle voice sums up as:
The difference between the active and middle is one of emphasis. The active voice emphasizes the action of the verb; the middle emphasizes the actor [subject] of the verb. “It, in some way, relates the action more intimately to the subject” (415) [Wallace is himself quoting here from H. E. Dana and J. R. Mantey, A Manual Grammar of the Greek New Testament (Toronto: Macmillan, 1927), 157].
He makes one of two special clarifications that is particularly relevant here (italics his, bolding my emphasis):
For Koine Greek, the term middle has become a misnomer, because it inherently describes that voice that stands halfway between the active and the passive. Only the direct middle truly does this (in that the subject is both the agent and receiver of the action). Since the direct middle is phasing out in Hellenistic Greek, the term is hardly descriptive of the voice as a whole (415).
So direct middles, where the subject is also receiving the effects of the action, while present in the NT, are only one of many uses, and so it is a mistake to assume that because a middle voice is present, it is reflexive upon the subject in a direct manner. As with many things, context should help answer that. But what are the possibilities then (his labels and my summary of Wallace):
- Direct (subject does the action directly and receives the action directly)
- Redundant (like direct, but has explicit reflexive pronoun and is primarily used with deponent verbs [or at least verbs that do not have a typical active form], so it needs the pronoun to communicate the middle idea as opposed to the active idea of a deponent).
- Indirect (subject acting in his/her own interest to benefit in indirect way from the action)
- Causative ("subject has something done for or to himself or herself" ; so it can be a direct or indirect idea for receiving action, but the action is actually done by another who or what is caused by the subject)
- Permissive ("subject allows something done for or to himself or herself" ; so it can be a direct or indirect idea for receiving action, but the action is actually done by another person allowed to do so by the subject)
- Reciprocal (only with plural subjects showing interaction between the individuals)
- Deponent (verbs that have not active form, but the middle form has an active meaning)
It seems safe to rule out redundant, deponent, and reciprocal right of the top, as it does not fit grammatically with the verb in question or the phrasing of the statement. Additionally, for purposes here, it does not matter if a causative or permissive idea is present, as each of those contain either a direct or indirect idea regarding the subject as the object of the action, and that is really the question for Heb 1:3:
Is Christ the direct recipient of purification of sins or is He indirectly benefiting from the purification of sins He enacts?
Hebrews itself makes it clear that Christ was "without sin" despite being tempted as all people are (Heb 4:15). So Heb 1:3 cannot be referring to Christ's own sins He committed, for He had none according to the author of Hebrews (cf. 2 Cor 5:21).
But could Heb 1:3 still be a direct reference to purging Himself of all the other people's sins he took upon Himself, for he "bear the sins of many" (Heb 9:28)? Yes, if context did not not indicate otherwise. Recall first that the purification discussed in chapters 9 & 10 is clearly the purification of believers, so the context already points toward an answer of the purification of others by the One Who is already pure. But this is further supported by two other contextual points:
- Hebrews makes it explicit that high priests are "appointed to act on behalf of men in relation to God, to offer gifts and sacrifices for sins" (Heb 5:1). So sacrifices made for sins by high priests are primarily for the benefit of others directly, stated so here in Hebrews and testified to in the Pentateuch. And Christ was appointed as a high priest by God (Heb 5:5).
Christ is specifically contrasted to other high priests that were "obligated to offer sacrifice for his own sins just as he does for those of the people" (Heb 5:3), but Christ's priestly duties began before He ever made his sacrifice of himself (Heb 5:7), and
He has no need, like those high priests, to offer sacrifices daily, first for his own sins and then for those of the people, since he did this once for all when he offered up himself (Heb 7:27),
and unlike the yearly offering when other high priests were "taking blood, which he offers for himself and for the unintentional sins of the people" (Heb 9:7), Christ was able to give His own blood (Heb 9:12), having no need of offering blood for His own sins because He was "without blemish to God" (Heb 9:14).
So Hebrews makes clear that Christ did not have to deal with His own sin directly (He had none) and in all places it refers to how the high priest is acting directly for other's when paralleling Christ's work with theirs, and that Christ was not affected by sin in any way that needed purifying of Himself—He was able to perform the priestly duties throughout His work, for He never failed to be "without blemish to God" in taking on sins to remove them permanently.
So the whole context of Hebrews points to an indirect middle with respect to what Christ receives by His purifying of sins.
Excursus (further grammatical support of an indirect middle)
The above argument is made without dependence on the Majority Text reading. But a comment needs addressing, and in addressing it, further grammatical points related to both minority and majority readings support the indirect middle. The comment below is:
The MT (Majority Text) says "having made purification of himself from our sins" which I don't think supports your case. The "of himself" is present in the middle voice. So it really doesn't jive with the idea of him "having made purification of our sins" as you suggest. So in no way can you get from either Greek text to his "purifying us".
There are a few flaws in that analysis.
- The the reflexive pronoun ἑαυτοῦ ("himself") in the MT reading is the object of the preposition διά ("διʼ ἑαυτοῦ"), and so is not specifically indicating either subject or object to the middle participle ποιησάμενος, and would not be translated "of himself" but rather "by himself" or "through himself" because of its association to the preposition (the genitive in association with the preposition loses its typical "of" idea to the preposition's controlling idea). The prepositional phrase is emphasizing Christ's role as actor (agent) in the "making" action, not as a receiver. The διʼ ἑαυτοῦ cannot be translated as the comment does in making simply the ἑαυτοῦ the object of the noun purification.
- For both majority and minority readings, it must be remembered that the actual grammatical direct object of the action of the middle participle here is the word purification (καθαρισμὸν) itself, as it is a noun in the accusative case (not an adjective nor a middle voice verb itself). So Christ (actor) is making (action) purification (receiver of the making action, i.e. it is what is being made). So Christ is not the explicit direct object of the middle voice verb here, which strongly favors an indirect middle voice idea is intended (as the context played out to show). It also argues directly against the ἑαυτοῦ being the object of the verbal "making." Still...
- It must be determined what is being purified from this cleansing away of sin. Purification is qualified (in all readings) as purification "of sins" (τῶν ἁμαρτιῶν). This has to have at least some sense of an ablative force, that is, the purification is "away from sin" (sin is what is being washed away), but may also be an objective genitive of the action of purification contained in the noun, as occasionally the "receiver" (object) of the cleansing action of the verb καθαρίζω refers to the filth/disease/etc. that is being cleansed away, not to the object that is being made clean (e.g. Mt 8:3 it is leprosy that is the subject of the passive form of the verb). So if "of sins" states what is being cleansed away, then it still remains as to what is being made clean. This is left unexpressed directly in the phrasing, as even the inclusion of the MT text of ἡμῶν ("our") in the genitive is clearly describing where the sins come from ("our sins"), whether that cleansing is of us from our sins or of Christ from our sins which He bore—which leads back to the contextual argument for it being "us" (i.e., believers), not Christ, that are cleansed.
So "having made purification of our sins" is indeed the MT reading, and as the NKJV puts it, the reflexive pronoun is in the agency "by himself," unlike the comment indicated for a translation of the MT text. But the MT reading does not itself resolve what is being cleansed away from the sins, which relies still upon the main contextual argument present for both majority and minority readings.
If an indirect benefit is to Christ, how does Hebrews indicate Christ benefited indirectly from dealing with sins? A few ways expressed are (I have no doubt this is not exhaustive of the Hebrews text, but is reflective of indirect benefits gained by purifying others from sin):
- He gained a brotherhood brought to glory (Heb 2:10-11; 3:1)
- He gained a victory over death (Heb 2:14-17)
- He gained greater glory (Heb 3:3)
God and Christ performed this act of purifying of sins in order to gain the sanctified people as part of "all things" they intended from the creation of the world (Heb 1:2).
More could be said, since Hebrews is so tightly integrated in its theology (one aspect depends upon another aspect, etc.; this aspect pictured in the OT by such and such, and this other aspect pictured by such and such, etc.), but I believe when chapters 9 & 10 are read as a whole, one can see how the atonement sacrifice of Christ relates to many points, but chiefly here, to the cleansing and thus sanctifying of the believers. This is the "purification of sins" referred to in Heb 1:3.