Nazir

On the view of R. Akiba, seeing that whether he be simply a High Priest or whether he be a High Priest who is also a nazirite, we can infer from 'for his brother' [that he may defile himself for a neglected corpse], what is the purpose of 'for his father and for his mother'? — They are both necessary. For were only his father mentioned, it might be thought that the reason why he may not defile himself for him is that there is merely a presumption [of paternity],  whereas for his mother who we know bore him, he should defile himself. Again, if the All-Merciful had mentioned his mother, it might be thought that he may not defile himself for his mother because her children['s descent] is not reckoned through her,  whereas for his father, since it has been affirmed, 'by their families, by their fathers' houses',  it might be said that he should defile himself. We are therefore told [that he may defile himself for neither]. [On the view of R. Akiba] what is the purpose of 'Neither shall he go in to any dead body'?  — To Part b