Nagakiyo KAGAMI of Kai-Genji (Minamoto clan) saw a limit to the power of Taira clan and decided to return to Togoku (the eastern part of Japan, particularly Kanto region) by asking TAIRA no Tomomori (the fourth son of TAIRA no Kiyomori) using an excuse of the illness of his elderly mother, but his request was not granted, but TAIRA no Moritsuna, who was the Takahashi no hangan (inspector - third highest of the four administrative ranks of the ritsuryo period) advised TAIRA no Tomomori 'not to force him to stay like Kenin' despite knowing his true intention and he finally gained permission from Tomomori.
要するに、平家を見限った甲斐源氏の加々美長清が、老母の病を口実に東国へ帰ろうと考え、それを平知盛（平清盛の四男）に申し出たところ許しては貰えなかったが、高橋判官平盛綱はその真意に気づきながらも、「家人のように抑留すべきでない」と平知盛に口添えをしてくれて、やっと知盛の許しを得たという話し。