Rashi on Genesis 17:14/רש"י על בראשית י״ז:י״ד

1וערל זכר AND THE UNCIRCUMCISED MALE — This phrase teaches that circumcision must be at that place where the distinction between male and female is evident (Genesis Rabbah 46:13).

2אשר לא ימול HE WHO DOES NOT CIRCUMCISE HIMSELF) as soon as he reaches the age when he is legally liable to punishment, ונכרתה THEN HE SHALL BE CUT OFF — his father, however, who did not have him circumcised is not punished on his account with כרת (excision, “being cut off from his people”), but is merely transgressing an עשה “a positive commandment” (for which the punishment is flagellation).

3ונכרתה הנפש THAT SOUL SHALL BE CUT OFF — i. e. he shall depart hence childless and shall suffer an untimely death.