 you said he had become accustomed to urging people to rights and to refraining from superfluous things until he began to use that in his poems after his letters and in his sermons after all his speech. among that is his saying about yahya bin khalid
وقلتم قد لزم الحث على الحقوق، والتزهيد في الفضول، حتى صار يستعمل ذلك في أشعاره، بعد رسائلة، وفي خطبه، بعد سائر كلامه؛ فمن ذلك قوله في يحيى بن خالد