27, 28. it shall be seven days under the dam--Animals were not considered perfect nor good for food till the eighth day. As sacrifices are called the bread or food of God (Le 22:25), to offer them immediately after birth, when they were unfit to be eaten, would have indicated a contempt of religion; and besides, this prohibition, as well as that contained in Le 22:28, inculcated a lesson of humanity or tenderness to the dam, as well as secured the sacrifices from all appearance of unfeeling cruelty.
JFB.
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