汾陽無德禪師語錄 2.155

2.155

Yaoshan instructed the assembly, saying, "Where wisdom does not reach, be sure to avoid speaking of it; if you speak of it, horns will sprout on your head."
Daowu immediately walked out.
Yunyan asked Yaoshan, "Why did Senior Brother Zhi not respond to the Venerable?"
Yaoshan said, "Rather, it is Zhi the ascetic who understands. Go and ask him."
[Yunyan] then went and asked Senior Brother Zhi, "Why did you not respond to the Venerable just now?"
He said, "I have a headache today. Go and ask the Venerable."
After Yunyan passed away, [Dao]wu said, "Yunyan did not know it exists. I regret not having told him at that time. Even though it was like this, after all he did not go against being a son of Yaoshan."