{a} This is the ordinance of the law which the LORD hath commanded, saying, Speak unto the children of Israel, that they bring thee a red heifer without spot, wherein is no blemish, and upon which never came yoke:

(a) According to this law and ceremony you shall sacrifice the red cow.

Wesley's Notes

19:2 Red - A fit colour to shadow forth the bloody nature of sin, and the blood of Christ, from which this water and all other rites had their purifying virtue. No blemish - A fit type of Christ. Upon which never came yoke - Whereby may be signified, either that Christ in himself was free from all the yoke or obligation of God's command, till for our sakes he put himself under the law; or that Christ was not forced to undertake our burden and cross, but did voluntarily chuse it. He was bound and held with no other cords but those of his own love.

Scofield Reference Notes

[1] red heifer

The red heifer: Type of the sacrifice of Christ as the ground of the cleansing of the believer from the defilement contracted in his pilgrim walk through this world, and illustration of the method of his cleansing. The order is:

(1) the slaying of the sacrifice;

(2) the sevenfold sprinkling of the blood, typical public testimony before the eyes of all of the complete and never-to-be-repeated putting away of all the believer's sin as before God. Heb 9:12-14 10:10-12.

(3) the reduction of the sacrifice to ashes which are preserved and become a memorial of the sacrifice;

(4) the cleansing from defilement (sin has two aspects--guilt and uncleanness) by sprinkling with the ashes mingled with water. Water is a type of both the Spirit and the Word. Jn 7:37-39. Eph 5:26. The operation typified is this: the Holy Spirit used the Word to convict the believer of some evil allowed in his life to the hindering of his joy, growth, and service. Thus convicted, he remembers that the guilt of his sin has been met by the sacrifice of Christ 1Jn 1:7. Instead, therefore, of despairing, the convicted believer judges and confesses the defiling thing as unworthy a saint, and is forgiven and cleansed Jn 13:3-10 1Jn 1:7-10.

Jamieson-Fausset-Brown Bible Commentary

2. This is the ordinance of the law-an institution of a peculiar nature ordained by law for the purification of sin, and provided at the public expense because it was for the good of the whole community.

Speak unto the children of Israel, that they bring thee a red heifer without spot, &c.-This is the only case in which the color of the victim is specified. It has been supposed the ordinance was designed in opposition to the superstitious notions of the Egyptians. That people never offered a vow but they sacrificed a red bull, the greatest care being taken by their priests in examining whether it possessed the requisite characteristics, and it was an annual offering to Typhon, their evil being. By the choice, both of the sex and the color, provision was made for eradicating from the minds of the Israelites a favorite Egyptian superstition regarding two objects of their animal worship.

Matthew Henry's Concise Commentary

19:1-10 The heifer was to be wholly burned. This typified the painful sufferings of our Lord Jesus, both in soul and body, as a sacrifice made by fire, to satisfy God's justice for man's sin. These ashes are said to be laid up as a purification for sin, because, though they were only to purify from ceremonial uncleanness, yet they were a type of that purification for sin which our Lord Jesus made by his death. The blood of Christ is laid up for us in the word and sacraments, as a fountain of merit, to which by faith we may have constant recourse, for cleansing our consciences.