John Gills Exposition of the Bible Commentary - Deuteronomy 21:4
The elders of that city shall bring down the heifer unto a rough valley ,.... Cities being generally built on hills, and so had adjacent valleys, to which there was a descent; but here a rough valley, or the rougher part of it, was selected for this purpose. As a valley is low, and this a rough one, it may be an emblem of Christ's being brought into this lower world, from heaven to earth, to do the will of his Father, which was to work out the salvation of his people; and of his coming into... read more
Matthew Henry's Complete Commentary - Deuteronomy 21:1-9
Care had been taken by some preceding laws for the vigorous and effectual persecution of a wilful murderer (Deut. 19:11-13), the putting of whom to death was the putting away of the guilt of blood from the land; but if this could not be done, the murderer not being discovered, they must not think that the land was in no danger of contracting any pollution because it was not through any neglect of theirs that the murderer was unpunished; no, a great solemnity is here provided for the putting... read more