This chapter would more naturally follow the 15th chapter of Leviticus. See the note to Leviticus 15:1.

And if she be not able. — As a merciful provision for those who were too poor to bring a lamb, the law permits them to br…

And if she be not able to bring a lamb
As everyone was not in circumstances sufficient to be at the expense of buyin…

After the laws concerning clean and unclean food, come the laws concerning clean and unclean persons. Man imparts his depraved nature to his offspr…