1) It is written in the Testament of R. Yehudah HaChassid that two men with the same names should not contract a marriage between their children. Some say that if one of them has only one name, and the other has two names, we need not be careful about it; also, if one is a Kohen and the other is a Levi or the like, we need not be careful about it. Some say that the whole precaution applies only to an uncommon name, i.e., both of them have the same uncommon name. But with common names such as Avraham, Yitzchak, etc., we need not be careful about it. Others are lenient about the entire matter, completely ignoring the fact that the two have the same name.