...who will devote oneself to kosen-rufu...

If you accomplish shakubuku and initiate a new member into Nichiren Shoshu Buddhism, it is essential that you support and nurture this new member to become a fine believer who will devote oneself to kosen-rufu as a soldier of shakubuku. [shakubuku means conversion; kosen-rufu means spread of the religion.]

Is "oneself" the correct pronoun? If not, can I use himself or herself?

Thanks.