Keizan Zenji, the mother of the Japanese Soto Sect, helped spread Zen to the masses by nurturing the construction of Temples, by developing prayers for health, wealth and good being and by developing a priestly class to conduct these services.
In time, the Soto Sect developed a unique plan for enlightened ancestors. At the time of one’s passing, the Priest gives the deceased a new name and the Soto precepts to start them on the path to becoming an enlightened ancestor. After a 49 year journey, if accompanied by appropriate services along the way, the deceased becomes an enlightened ancestor. If the services are not done, the deceased winds up in Hell. Thus, the Soto Zen Priest has a very important function in helping the deceased reach enlightened ancestorship. My teacher, Maezumi Roshi, did not appraise me of this priestly role. I learned about it from Nara Sensei (previous head of the Soto Sect University, Komazawa) who has published a paper on this system (he claims it is unique among the Buddhist countries.)
In Japan this has basically become the only function of the Temple Priest, funerals and memorial services. Priests are not trained in individual or family counseling.
In the Japanese Soto School, you have to be a Priest to become a Zen Teacher. That is, you have to have the ceremony of Denkai (Full Priest) before having the ceremony of Denbo or Shiho (Dharma Transmission.)