Neither is it possible that the other bird, which was set at liberty, should represent the leper as healed, and its release, his liberation; however plausible, at first thought, this explanation may seem. For the very same ceremony as this with the two birds was also to be used in the cleansing of a leprous house (vv. 50-53), where it is evident that the loosing of the living bird could not have any such significance; since the notion of a liberty given would be wholly inapplicable in the case of a house. But whatever the true meaning of the symbolism may be, it is clear that it must be one which will apply equally well in each of the two cases, the cleansing of the leprous house, no less than that of the leprous person.
We are therefore compelled to regard the slaying of the one bird as a true sacrifice. No doubt there are difficulties in the way, but they do not seem insuperable, and are, in any case, less than those which beset other suppositions. It is true that the birds are not presented before Jehovah in the tabernacle; but as the ceremony took place outside the camp, and therefore at a distance from the tabernacle, this may be explained as merely because of the necessity of the case. It is true, again, that the choice of the bird was not limited, as in the tabernacle sacrifices, to the turtle-dove or pigeon; but it might easily be that when, as in this case, the sacrifice was elsewhere than at the tabernacle, the rules for service there did not necessarily apply. Finally and decisively, when we turn to the law for the cleansing of the leprous house, we find that atoning virtue is explicitly ascribed to this rite with the birds (ver. 53): "He shall make atonement for the house."
But sacrifice is here presented in a different aspect from elsewhere in the law. In this ceremonial the central thought is not consecration through sacrifice, as in the burnt-offering; nor expiation of guilt through sacrifice, as in the sin-offering; nor yet satisfaction for trespass committed, as in the guilt-offering. It is sacrifice as procuring for the man for whom it is offered purity and life, which is the main thought.
But, according to vv. 52, 53, the atonement is made with both the dead and the living bird. The special thought which is emphasised by the use of the latter, seems to be merely the full completeness of the work of cleansing which has been accomplished through the death of the other bird. For the living bird was represented as ideally identified with the bird which was slain, by being dipped in its blood; and in that it was now loosed from its captivity, this was in token of the fact that the bird, having now given its life to impart cleansing and life to the leper, has fully accomplished that end.
Obviously, this explanation is one that will apply no less readily to the cleansing of the leprous house than of the leprous person. For the leprosy in the house signifies the working of corruption and of decay and death in the wall of the house, in a way adapted to its nature, as really as in the case of the person; and the ceremonial with the birds and other material prescribed means the same with it as with the other,--namely, the removal of the principle of corruption and disease, and impartation of purity and wholesomeness. In both cases the sevenfold sprinkling, as in analogous cases elsewhere in the law, signified the completeness of the cleansing, to which nothing was lacking, and also certified to the leper that by this impartation of new life, and by his cleansing, he was again brought into covenant relations with Jehovah.
With these ceremonies, the leper's cleansing was now in so far effected that he could enter the camp; only he must first cleanse himself and his clothes with water and shave his hair,--ceremonies which, in their primary meaning, are most naturally explained by the importance of an actual physical cleansing in such a case. Every possible precaution must be taken that by no chance he bring the contagion of his late disease into the camp. Of what special importance in this connection, besides the washing, is the shaving of the hair, will be apparent to all who know how peculiarly retentive is the hair of odours and infections of every kind.