Ken Cohen: we have absolutely no indication, and no tradition, of what the religious beliefs of Bilhah and Zilpah were, or which deity or deities they worshipped.
betsy teutsch: Some of the rejection of Bilhah and Zilpah is due to class and race issues. Bilhah and Zilpah should not be treated merely as objects (wombs/surrogates) but as putting their lives on the line for Israel in enduring pregnancies for the propagation of the tribes. Bringing the rare practice of including B&Z enhances pluralism. Inclusion of Bilhah and Zilpah as equals with Rachel &Leah is a way of retroactively treating them justly as mothers.
