Exodus 12:39; Exodus 16:23
They baked the dough which they had brought out of Egypt into cakes of unleavened bread. For it had not become leavened, since they were driven out of Egypt and could not delay, nor had they prepared any provisions for themselves.
then he said to them, "This is what the LORD meant: Tomorrow is a sabbath observance, a holy sabbath to the LORD . Bake what you will bake and boil what you will boil, and all that is left over put aside to be kept until morning."