firstling of an ass 13:13 firstling of an ass. As an unclean
animal, the ass was not suitable as a sacrifice, but was a
valuable animal for service. Since every firstborn animal was
henceforth to be sacrificed, the firstborn of an ass must either
be slain and discarded, or else redeemed by a sacrificial lamb.
The firstborn son of Israelite parents also had to be redeemed
by a lamb.