Nedarim 8 - Good advice from Rav Gidel
The last advice we learned on the previous page came from Rav Gidel (in the name of Rav). Let us see some more of Rav Gidel's advice.
It is commendable to take an oath to do a mitzvah. Even though one is already under an oath to do mitzvot, since the Jewish people have accepted this oath as a whole, it is still OK to do more. We learn it from King David, who said "I swore and I will perform Your righteous mitzvot."
He also said that one who saw in a dream himself being excommunicated should find ten scholars to lift the ban from him. These should be people able to reason, not just retell the laws. But if one can't find such scholars, those who know the law will also do. And if one cannot find even these, he should sit on the crossroad and greet every person with "Peace be unto you." After ten passers by will return his greeting with "Peace unto you," his ban is lifted.
Art: King David by Gustave Moreau