"And if one curses his father and his mother": This ("and") tells me (that he is liable) for cursing only his father and his mother (together). Whence do I derive the same for (cursing) his father and not his mother, or his mother and not his father? From (Leviticus, Ibid.) "His father or his mother he has cursed" — in any event (i.e., either one.) These are the words of R. Yoshiyah.