Parshas Ki Setzei
“You may not take the mother on the children; You must surely send the mother away and take the children for yourself!” (Devarim 22:6-7)
It is a negative commandment that one may not remove the nest of a bird-the mother with the fledglings or the eggs. Instead, one must send the mother away. About this it says “You may not take the mother on the children!”.
It is a positive commandment that one must send the mother away from the nest before taking the chicks, as it says “You must surely send the mother away and take the children for yourself!”.
Amongst the roots of this commandment are that we must consider in our hearts the way that Hashem looks after the human race in particular and all of His creations in general. This means to say that Hashem wishes the continued existence of each specie that He created, and He will therefore never annihilate a specific specie. When a person considers this he will understand the ways of Hashem and he will see that the continuation of the species in this world in the way that none will be destroyed. A person will also know that when he keeps all of the commandments of Hashem and straightens out all his path and has clean hands and a pure heart, then Hashem will personally look after him and his body will live long in this world and his soul will live forever in the next. About things like this Chazal said that this is tit-for-tat as when a person considers that all of his existence and all of the good that he has comes about only because Hashem is looking after him and for no other reason whatsoever, he will also merit that Hashem will turn towards him with goodness and support him. In return for him believing in the Creator regarding the matters of supporting everything and the omnipotence of Hashem, Chazal said that a person receives children. This means to say that his existence will be continued as children are the continued existence and memory of a person.
This commandment applies in all places and at all times both to men and to women. One who takes a mother bird with its children has transgressed both a positive and a negative commandment. If he then sends the mother away, he has rectified the transgression of the negative commandment, whereas if the mother dies before he sends it away or somebody else sent it away, there is no way to repair what he has done.