It's because they have a different ordination. In most traditions, monks are ordained following the Vinaya or discipline sutras. These include vows of celibacy.
In Japan, starting in the ninth century, they began a new form of ordination based on the bodhisattva vow. Saichō was responsible for starting this tradition of basing it on the bohisattva vow.
In this tradition, they don't take a vow of celibacy, so can get married.
For the history see A Brief History of the Buddhist Precepts in Medieval Japan
For another view on it:
There are other traditions of Buddhism that base the ordination on the bodhisattva vows. Especially Thích Nhất Hạnh with his "order of interbeing". But his monks and nuns are celibate.
I don't know much about this subject and there are confusing conflicting things on the internet about it.
But basically, in general way, it is because it's based on the Mahayana and the bodhisattva vow, rather than the Vinaya, and then also, on awakening to the true nature of mind as well, a vow basically to wake up :).
In any of the other traditions, a monk or nun can give up their vows at any time, and it is a simple process. They just need to say that they are giving up their robes to anyone of sound mind able to understand what they are saying. After that they can get married, but would no longer be a monk or nun,
In Japan, starting in the ninth century, they began a new form of ordination based on the bodhisattva vow. Saichō was responsible for starting this tradition of basing it on the bohisattva vow.
In this tradition, they don't take a vow of celibacy, so can get married.
For the history see A Brief History of the Buddhist Precepts in Medieval Japan
For another view on it:
"The Buddhist monk Saichô (767-822) dared to abrogate the multitude of traditional small precepts in favour of the sole precept to «awaken to the fundamental one-mind of Mahayana. He established a ceremony for the taking of this precept and built a Mahayana ordination platform for the purpose on Mount Hiei near Kyoto. Since then, various branches of Japanese Buddhism have adhered to this. But Zen, following in the steps of its Chinese tradition, upheld an original structure of mutual complementarity of the monastic and secular communities and thus did not completely give way to lay Buddhism. Although this was a contradictory compromise of a kind that is again different from that of Southeast Asian Buddhism, one can say that the realization of this kind of contradiction bears potential for the future. However, it also proved to be a cause for confusion in monastic Japanese Buddhism."
the View of a Zen Monk from Japan
There are other traditions of Buddhism that base the ordination on the bodhisattva vows. Especially Thích Nhất Hạnh with his "order of interbeing". But his monks and nuns are celibate.
I don't know much about this subject and there are confusing conflicting things on the internet about it.
But basically, in general way, it is because it's based on the Mahayana and the bodhisattva vow, rather than the Vinaya, and then also, on awakening to the true nature of mind as well, a vow basically to wake up :).
In any of the other traditions, a monk or nun can give up their vows at any time, and it is a simple process. They just need to say that they are giving up their robes to anyone of sound mind able to understand what they are saying. After that they can get married, but would no longer be a monk or nun,
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Robert Walker
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