Honen followed Shan-tao’s words almost exactly to the letter. He said that although humans have Buddha-nature, in the age of the Final Dharma, they cannot develop it through their own practice.
Therefore, they should recognize through Nembutsu practice that they are existentially “ordinary persons,” in other words, that it is important to return to ignorance.
This return, however, does not imply an ignorance which follows whims, delusions and passions. Rather, this return points to the lack of fundamental importance that the knowledge we learn through study serves in gaining enlightenment.