Deuteronomy 21:3

And it shall be, that the city which is next unto the slain man,.... And so suspected, as the Targum of Jonathan, of the murder; or the murderer is in it, or however belonged to it:

even the elders of the city shall take an heifer; of a year old, as the same Targum, and so Jarchi; and in this the Jewish writers agree, that it must be a year old, but not two; though heifers of three years old were sometimes used in sacrifice, Genesis 15:9 a type of Christ, in his strength, laboriousness, and patience; see Numbers 19:2

which hath not been wrought with; in ploughing land, or treading out corn:

and which hath not drawn in the yoke, which never had any yoke put upon it; or however, if attempted to be put upon it, it would not come under it, and draw with it: no mention is made, as usual, that it should be without blemish: because though in some sense expiatory, yet was not properly a sacrifice, it not being slain and offered where sacrifices were; hence it is said in the Misnah q, that a blemish in it did not make it rejected, or unlawful for use: nevertheless, this heifer may be a type of Christ, whose sufferings, bloodshed, and death, atone for secret and unknown sins, as well as for open and manifest ones, even for all sin; and its being free from labour, and without a yoke, may signify the freedom of Christ from the yoke of sin, and the service of it, and from human traditions; that he was not obliged to any toil and labour he had been concerned in, or to bear the yoke of the law, had he not voluntarily undertaken it of himself; and that he expiated the sins of such who were sons of Belial, children without a yoke; and for the same reason, this heifer not being required to be without blemish, might be because Christ, though he had no sin of his own, was made sin for his people, and reckoned as if he had been a sinner; though indeed, had this been the design of the type, all the sacrifices which typified Christ would not have required such a qualification, to be without blemish, as they did.

q Ut supra, (Sotah, c. 9.) sect. 5.