For Nichiren, Śākyamuni Buddha surpasses our worldly rulers, teachers, and parents, because he is the lord who presides over our awakening, the teacher who leads us to awakening, and the parent who sees us as his children and who are the inheritors of his awakening.

Śākyamuni Buddha is equipped with the three virtues of a lord, master, and parent. As a lord, he protects the people; as a teacher he guides the people; and as a parent, he loves the people. It is only he who is perfectly equipped with these three virtues. (Hori 2004, p. 244 modified. See also Gosho Translation Committee 2006, p. 1039)

When Nichiren spoke of repaying debts of gratitude to our rulers, teachers, and parents, he also means that we must realize and requite our debt of gratitude to the Eternal Śākyamuni Buddha above all, and in doing so repay the worldly debts as well.