Rather we must say that Netzach-Hod-Yesod come at the beginning of the Pregnancy, as soon as the embryo has taken its form forty days after conception. Just as we see that a person’s mental powers of Chochmah-Binah-Daat develop gradually in childhood until he attains full Daat at the age of thirteen (thus becoming liable for his actions), similarly, throughout the period of Pregnancy Chessed-Gevurah-Tiferet enter gradually and then, at the very moment of birth, they become revealed completely.
What was built during the Pregnancy is completed during the first twenty-four months of Suckling, this being the period of the purification of Hod-Yesod-Malchut. (As discussed below, although a child has legs at birth, he is unable to walk until later.) From the conclusion of these twenty-four months until thirteen years, Chochmah-Binah-Daat begin to enter, but the entire period from birth until thirteen years – Suckling (יניקה, yenikah) and childhood (קטנות, katnut) – is called that of Chessed-Gevurah-Tiferet. For these are revealed at birth and during this period become increasingly ready to receive Chochmah-Binah-Daat over them. Then at Maturity, Chochmah-Binah-Daat enter completely, and accordingly the period after thirteen years is called Maturity (גדלות, gadlut.) Thus the proposition goes on to state: