父親はさ、俺には……如何にも職業が教師といえば納得される感じの清廉潔白な厳しさがあるしつけをした。
The character's father is a teacher and he's describing how hew was raised. I am struggling with the combo of いえば + passive 納得される. My reading is that he says his father discipline him in a way a teacher would, but why is the passive used?
"If you were to say teacher you'd receive understanding" kind of deal?
The subjects of いう and 納得される are unspecified, but they are the same person. 職業が教師(だ)という is not "say teacher" but "say that my/his profession is a teacher".
職業が教師といえば納得される。
If he says his profession is a teacher, he will be understood.
If I say his profession is a teacher, I will be understood.
If one says his profession is a teacher, they will be understood.
Assuming the subject is the speaker's father:
如何にも職業が教師といえば納得される感じの清廉潔白な厳しさ
incorruptible strictness that is exactly like "if he says his profession is a teacher, he will be understood"
But you can rephrase this phrase without specifying who said "教師(だ)":
incorruptible strictness that indeed makes one agree when told his profession is a teacher
Note that 如何にも modifies 納得される感じ(だ).
