Deut 21:1

21:1 If . . . someone is found slain. In the case of an unsolved murder, the elders from the nearest town were to take an oath of innocence and ignorance. The symbolism of the heifer, killed while the oath was taken, is clear: it dies as a symbol of the murderer who ought to die. The land was to be purged of serious guilt. The vicarious death of the heifer points to the death of Christ as a satisfaction for the sins, known and unknown, of His people.