Deuteronomy 22:6

If a bird's nest chance to be before thee in the way in any tree, or on the ground, whether they be young ones, or eggs, and the dam sitting upon the young, or upon the eggs, thou shalt not take the dam with the young:

If a bird's nest chance to be before thee in any tree, or on the ground,.... Which are the usual places in which birds build their nests; and this, as Jarchi observes, excepts such nests that are prepared, that is, that are purposely made for fowls kept at home; and with which agrees the Jewish canon, which says {t}

"the letting go (the dam out of) the nest is not used but of a fowl, and it is not used but of what is not prepared; what is that which is not prepared? such as geese and hens, whose nest is in an orchard; but if their nest is in the house, and so doves kept at home, a man is free from letting (the dam) go;''

that is, he is not obliged to let it go; and this is to be understood of clean birds only; so the Targum of Jonathan,

"the nests of clean birds;''

agreeably to the same canons and the explanation of them {u},

"an unclean bird is free from letting go; so an unclean bird, that sits upon the eggs of a clean bird, also a clean bird that sits upon the eggs of an unclean bird, are free from letting go,''

or persons are not obliged to let such go:

whether they be young ones or eggs; that are in the nest; and the Jewish canon is {w},

"if there is but one young one, or one egg, a man is obliged to let go the dam, as it is said a nest: a nest is a word of a large sense:''

and the dam sitting upon the young or upon eggs, thou shalt not take the dam with the young; according to the above canon,

"if she is flying at the time her wings reach the nest, a man is bound to let her go; but if her wings touch not the nest, he is free from letting her go--if the young ones are capable of flying, or the eggs rotten, he is free from letting her go, as it is said, and the dam sitting, &c. as the young are alive, so the eggs must be firm and sound, rotten ones are excepted; and as eggs have need of their dam, so the young have need of their dam; those (therefore) that can fly are excepted:''

the dam is not to be taken with her young upon any account; yea, it is said {x}, not even to cleanse a leper; and whoever does take her is to be beaten: this law was made partly to preserve the species of birds, and prevent the decrease of them; for a dam let go might breed again, and to this purpose are the verses ascribed to Phocylides {y}, which contain the substance of this law, and this reason of it: and partly, as Maimonides observes {z}, that the dam might not be afflicted at the sight of the spoil of her young; for this law does not prohibit the taking of her in any other place but in her nest, nor after her young are taken, but not together; and, as the same writer remarks, if the law would have such care taken of beasts and birds, that they might be freed from sorrow and distress, how much more of man? Wherefore the intention of this law is to teach humanity, compassion, and pity in men to one another, and to forbid cruelty, covetousness, and such like vices; as also to instruct in the doctrine of Providence, which has a respect to birds; and our Lord may be thought to have this law in view, Luke 12:6.

{t} Misn. Cholin, c. 12. sect. 1.
{u} Ib. sect. 2.
{w} Ib. sect. 3.
{x} Misn. Cholin, c. 12. sect. 5.
{y} mhde tiv orniyav, &c. Poem. admon. l. 80, 81.
{z} Moreh Nevochim, par. 3. c. 48.