If a woman has conceived and born (Lev. 12:2)
This section of the Torah, which deals with the laws of childbirth, comes directly after that portion which spoke of unclean animals--those which died of themselves, creeping things and insects. We learn from this that in the same way that eating non-kosher food makes a Jew dulled and insensitive to holiness, the opposite is true. Keeping the laws of kashrut ensures that one’s children will be spiritually healthy and sound. (Ramban)
If a man shall have on the skin of his flesh (Lev. 13:2)
When discussing the phenomenon of leprosy and the various appearances such a plague could assume, the Torah uses the word adam--man--a term reserved for expressing man’s finest attributes and characteristics. Why doesn’t the Torah use any of the three other Hebrew words for man--ish, gever, or enosh?
The plague of leprosy appeared only “on the skin of his flesh”--on the most external part of a person. Years ago, when G-d afflicted someone with leprosy as a punishment for his deeds, it affected only his most external self, for the inner person was spiritually healthy and not deserving of punishment. Nowadays we have no such phenomenon, as the Biblical leprosy differed form the modern-day disease bearing the same name. In our time, it’s not just the external part of ourselves we must work on and purify. (Sefer Maamarim)
And the priest shall see the plague (Lev. 13:3)
The Talmud cautions that a priest who is blind in one eye is excluded from examining and pronouncing judgment on plagues. Every plague deserves to be studied with two eyes. One eye sees the leprosy itself, and the other eye sees the extenuating circumstances and reason which led to the sin. A priest who is blind in one eye will see only that which is negative, the plague itself, and will not try to find a merit in that person’s favor. Such a priest is unfit to pass judgment. (Rabbi Yosef Klein)