I became a Catholic 10 years ago. Since then, I myself checked why Japan had such a small Catholic and Christian population. I read several articles on the net, including those written by religious scholars. I talked about it with a very educated Protestant Christian. I visited Catholics Memorial museum in Nagasaki where I made a pilgrimage last year.
So far these are my knowledge and understanding. For accurate facts, please check the appropriate books and other materials. Don’t refer them as a reliable source. Rather please use it as a starting point of your studying.
1.Christianity came too late.
It was already 16th century when St.Francis Xavier visited Japan.
Japan already had hundred years of history imbued with Buddhism and Shintoism in all aspects of life.
While Western nations successfully integrated Christianity in politics and even in military,
Japanese warlords only could allow it as an observer or forbid it.
Perhaps things would have been different if Christianity was there before establishment of samurai rule.
2.Western ambition and arrogance.
A Japanese translator once overheard in Japanese ocean port foreign people’s conversation about colonial expansion into Japan and bringing Christianity together. It was Spanish plot to control the population through religion first and send armies and conquer. The translator took this message back to the Shogun (Hideyoshi) who took it seriously. In this Shogunate period, a Spanish soldier who landed on Japan was heard saying, our nation can conquer a such a small island with little effort, with derision (something like this), which was recorded and communicated to Shogun who was infuriated by the foreigner’s arrogance. Hideyoshi was also enraged that Japanese men and women were sold to foreign ships stationed in Japanese water. He perceived this trade was related to Christian preaching activity. So he ordered complete shutdown of Christian preaching in Japan.
3.Christianity’s intolerance toward other religions
Hideyoshi wasn’t so critical about Christianity from the beginning. Added to the reasons above was Christianity’s intolerance toward Buddhism and Shintoism. He grew dislike of Christianity.
4.Bible teaches that Lord Jesus is the supreme authority over the mankind
After Hideyoshi Shogunate was overthrown and new Tokugawa Shogunate was established, Tokugawa blood line also persecuted Christians harshly. Tokugawa Shogunate established the first sole sovereign rule over the entire Japan island and saw themselves as the absolute authority. They didn’t like Christianity that taught Lord Jesus was above them and the followers had to obey Lord Jesus first. There was a one big military revolt by Christians in southern Japan which very much astonished them.
5.Ocean protected Japan island from foreign invasions
When people are of homogeneous race and there is no foreign invasion, they can live in peace without belief in Absolute Existence (or any religion). Generally, people tend to look for divine help in time of danger.
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