Kabbalah su Levitico 23:2

Regarding what was said about "the mother laying on her chicks": Israel chirps to her with several chirps of prayer, and therefore she does not need to come down to them. So what does Israel do? They take the mother, which is the shekhina, and they tie her with the knot of the tefillin. When they arrive at the recitation of the Shema, her children call out with the 60 words of unity which are "Shema Yisrael Adonai Elohenu Adonai Eḥad". They go down to the mother and tie her to us. This is the meaning of "that you call them". This is "answering", as with the festivals.