He shall purify himself with it - יתחטא בו yithchatta bo, literally, he shall sin himself with it. This Hebrew form of speech is common enough among us in other matters. Thus to fleece, to bark, and to skin, do not signify to add a fleece, another bark, or a skin, but to take one away; therefore, to sin himself, in the Hebrew idiom, is not to add sin, but to take it away, to purify. The verb חטא chata signifies to miss the mark, to sin, to purify from sin, and to make a sin-offering. See the note on Genesis 13:13.

The Hebrews generally sacrificed males, no matter of what color; but here a heifer, and a heifer of a red color, is ordered. The reason of these circumstances is not very well known.

"The rabbins, with all their boldness," says Calmet, "who stick at nothing when it is necessary to explain what they do not understand, declare that the cause of this law is entirely unknown; and that Solomon, with all his wisdom, could not find it out."

Several fathers, as well modern as ancient, profess to understand the whole clearly.

1. The red heifer with them signifies the flesh of our Lord, formed out of an earthly substance.

2. Being without spot, etc., the infinite holiness of Christ.

3. The sex of the animal, the infirmity of our flesh, with which he clothed himself.

4. The red color, his passion.

5. Being unyoked, his being righteous in all his conduct, and never under the yoke of sin.

6. Eleazar's sacrificing the heifer instead of Aaron, Genesis 13:3, signifies the change of the priesthood from the family of Aaron, in order that a new and more perfect priesthood might take place.

7. The red heifer being taken without the camp (Genesis 13:3) to be slain, points out the crucifixion of our Lord without the city.

8. The complete consuming of the heifer by fire, the complete offering of the whole body and soul of Christ as a sacrifice to God for the sin of man: for as the heifer was without blemish, the whole might be offered to God; and as Christ was immaculate, his whole body and soul were made a sacrifice for sin.

9. As the fire of this sacrifice ascended up to God, so it points out the resurrection and ascension of our blessed Lord.

10. And as the ashes of this victim communicated a legal purity to those who were defiled, so true repentance, signified by those ashes, is necessary for the expiation of the offenses committed after baptism.

continued...

He shall purify himself with it,.... That is, with the ashes of the water of purification made of them: and this was to be done first

on the third day; from the time of his touching the dead body. Aben Ezra intimates, that there is a secret or mystery in this and the following number seven; it may respect the third day of Christ's resurrection, who, as he shed his blood for the expiation and purification of sinners, so he rose again the third day for the justification of them:

and on the seventh day he shall be clean; which may denote the perfect state, or sabbath of rest, which remains for the people of God, when all Christ's purified and justified ones shall be clear of all sin, and be the spirits of just men made perfect:

but if he purify not himself the third day, then the seventh day he shall not be clean; whoever is not cleansed from his sins by the blood of Christ, shed for the remission of them, and is not justified from them by him that rose from the dead the third day, will never be cleansed in the world to come, or in the eternal sabbath; but it will then be said, "let him that is filthy be filthy still", Revelation 22:11.

He shall purify himself {f} with it on the third day, and on the seventh day he shall be clean: but if he purify not himself the third day, then the seventh day he shall not be clean.

(f) With the sprinkling of water.

19:12 With it - With the water of separation. On the third day - To typify Christ's resurrection on that day by which we are cleansed or sanctified.

12. He shall purify himself . the third day-The necessity of applying the water on the third day is inexplicable on any natural or moral ground; and, therefore, the regulation has been generally supposed to have had a typical reference to the resurrection, on that day, of Christ, by whom His people are sanctified; while the process of ceremonial purification being extended over seven days, was intended to show that sanctification is progressive and incomplete till the arrival of the eternal Sabbath. Every one knowingly and presumptuously neglecting to have himself sprinkled with this water was guilty of an offense which was punished by excommunication.

19:11-22 Why did the law make a corpse a defiling thing? Because death is the wages of sin, which entered into the world by it, and reigns by the power of it. The law could not conquer death, nor abolish it, as the gospel does, by bringing life and immortality to light, and so introducing a better hope. As the ashes of the heifer signified the merit of Christ, so the running water signified the power and grace of the blessed Spirit, who is compared to rivers of living water; and it is by his work that the righteousness of Christ is applied to us for our cleansing. Those who promise themselves benefit by the righteousness of Christ, while they submit not to the grace and influence of the Holy Spirit, do but deceive themselves; we cannot be purified by the ashes, otherwise than in the running water. What use could there be in these appointments, if they do not refer to the doctrines concerning the sacrifice of Christ? But comparing them with the New Testament, the knowledge to be got from them is evident. The true state of fallen man is shown in these institutions. Here we learn the defiling nature of sin, and are warned to avoid evil communications.