Commentaries:
The firstborn of all clean, male animals (cattle, sheep, goats, etc.) were God's, and they were to be sacrificed to Him. Amazingly, these animals appear to represent the Egyptian firstborn (verse 14), and thus represent a sin offering for us.
John Plunkett
The Law of the Firstborn
Related Topics:
The word redeem means "buy back." If a family's firstborn donkey was critical to their livelihood, they could buy it back from God by offering a lamb in its place. Of course, God did not demand that His people offer their firstborn children as literal human sacrifices. They, too, were to be bought back by means of a lamb sacrifice.
John Plunkett
The Law of the Firstborn
Library resources that contain this verse: