Hammad bin Zayd حماد بن زيد بن درهم الأزدي الأزرق · Knowledge (Kitab Al-Ilm)

The Prophet (ﷺ) said: If anyone is given a legal decision ignorantly, the sin rests on the one who gave it. Sulayman al-Mahri added in his version: If anyone advises his brother, knowing that guidance lies in another direction, he has deceived him. These are the wordings of Sulayman.