Hello everybody!

I have been looking at the forum messages and I read some of the books that are listed and now I have my first question.
During our zazen sessions we have to try to suppress our dualistic thinking but, when zazen ends, we have to suddenly turn on again
our "dualistic mode": we have to choose between good and bad to observe the five precepts!

How can these two opposite (dualistic mode "on" again!) things can walk together?

Thank you in advance for every kind effort in giving me the "solution"

P.S.: if my English sounds strange it is because English is not my first language, so feel free to correct me!