1. A person should not take a mother bird away from its eggs, even for the purification process of a Metzora.
2. The Mishnah emphasizes the lesson from this law (#1).
3. Rebbi Yakov taught that the long life promised as a reward for Mitzvos is primarily in Olam ha'Ba.
4. A person generally does not receive punishment if he merely thinks about performing a sin.
5. People sent to do Mitzvos generally do not get harmed when they go and when they come back.
A BIT MORE
1. Part of the purification process of a Metzora involves slaughtering two birds. However, the Mishnah states that one may not take the mother bird away in violation of Shilu'ach ha''Ken, even for this purpose.
2. If we see that even an easy Mitvzah that does not require much sacrifice is rewarded by a long life, how much greater is the reward for the difficult Mitzvos!
3. This is because it is possible that a person fulfills these Mitzvos but then dies soon afterwards. It must be that the main reward is long life in Olam ha'Ba.
4. The exception is having thoughts of idolatry, for which one does receive punishment.
5. However, if the place they are going to or coming from is fraught with danger, they may still be harmed.