열왕기하 10:37의 Musar

And even though he had rendered a great favor to Israel, for Achav had served the Ba'al and the calves, and Yehu had abolished Ba'al worship from Israel and made [their sites] sewers, as Scripture states (II Kings 10:27), and he had also found favor in the eyes of the L-rd for having killed Achav (for which the kingdom was given him for four generations as mentioned in Scripture), and Yehu's later idol worship was unwitting, (as written in Sanhedrin 102a): "Yehu was a great tzaddik … but he saw the signature of Achiya Hashiloni and erred" — in spite of all this, since there remained in him part of the sin of Achav, he was punished, as is written in the beginning of Hoshea (1:4): "And I will remember the blood of Yizre'el (i.e., the blood of the house of Achav, whom he had killed in Yizre'el) on the house of Yehu." And from the words of Semak we learn that the same applies in all similar instances between man and his neighbor. If one punishes his friend with any manner of punishment — by striking [him] or "whitening" his face or by speaking lashon hara against him — even if in this, the din were in accordance with the shamer or the speaker — still, he must "know in his soul" that if he himself had transgressed in this way in the past or if he will transgress in this way in the future, then the suffering of this man whose face he whitened or against whom he spoke lashon hara will be reckoned "innocent blood," and he will be punished for it, just as if he had acted thus against a man complete in the Torah of the L-rd and His mitzvoth.