Dokai was rejected from being given a purple Buddhist priest stole and the title of master by the Emperor Kiso and was exiled to Shishu (Shandong Province), which turned out to be a blessing in disguise for the Soto sect to spread in Northern China.
道楷は、徽宗皇帝からの紫衣と師号の下賜を拒絶して、淄州（山東省）に流罪となり、災い転じて福となり、それが華北に曹洞宗が拡大する契機となった。