Page "Mamzer" Paragraph 6

The Talmud indicates that the term mamzer applied to the descendants of specific illicit unions.

In some cases, where the male parent was a Kohen ( a member of the priestly lineage of Aaron ) there is a related category called chalal.

According to the Mishnah a mamzer is the offspring of a Biblically forbidden union ( M. Yebamoth 4, Mishnah 13: " כל שחיבין עליו כרת בידי שמים ".

According to the Shulhan Arukh a mamzer can only be produced by two Jews ( Shulhan Arukh Even haEzer 4: 19 ).