Eliyahu HaNavi and bris

Question

Someone once told me that when Eliyahu HaNavi comes to a baby's bris, everyone who is presently there is forgiven for their sins.

Does anyone know the source for this?

Answer 1

Bnai Yissaschar Tishrei 4:2:7 mentions regarding all those attending a Bris receiving forgiveness for their sins in the name of a Medrash, however he says he has not seen where this Medrash is.

כך שמעתי שיש באיזה מדרש ולא ראיתיו

Rabbeinu Bachya Lech Lecha - 4th line from the bottom says that the Blood of Milah is a Kappara. See also the following page at the top where he says that since it is a Kappara therefore we make a Seuda.