And the people of Israel journeyed from Rameses to Succoth, about six hundred thousand men on foot, besides women and children. A mixed multitude also went up with them, and very much livestock, both flocks and herds. And they baked unleavened cakes of the dough that they had brought out of Egypt, for it was not leavened, because they were thrust out of Egypt and could not wait, nor had they prepared any provisions for themselves. The time that the people of Israel lived in Egypt was 430 years. At the end of 430 years, on that very day, all the hosts of the LORD went out from the land of Egypt. It was a night of watching by the LORD, to bring them out of the land of Egypt; so this same night is a night of watching kept to the LORD by all the people of Israel throughout their generations. And the LORD said to Moses and Aaron, "This is the statute of the Passover: no foreigner shall eat of it, but every slave that is bought for money may eat of it after you have circumcised him. No foreigner or hired worker may eat of it. It shall be eaten in one house; you shall not take any of the flesh outside the house, and you shall not break any of its bones. All the congregation of Israel shall keep it. If a stranger shall sojourn with you and would keep the Passover to the LORD, let all his males be circumcised. Then he may come near and keep it; he shall be as a native of the land. But no uncircumcised person shall eat of it. There shall be one law for the native and for the stranger who sojourns among you." All the people of Israel did just as the LORD commanded Moses and Aaron. And on that very day the LORD brought the people of Israel out of the land of Egypt by their hosts.
Exodus 12:37-51
The first recorded act of the emancipated people was to bake unleavened cakes (39) of the dough they had brought forth out of Egypt, and this is surely symbolic of the separated and simple life they were meant to lead as the pilgrim people of God. We can hardly doubt that at least to begin with the children of Israel responded to the spiritual implications of their deliverance, and that their hearts were really towards God (it was only later that their murmuring became such a tragic evidence of spiritual sickness). And this may well account for the fact that so many who were not of Israel companied with them. It is not surprising that there should be many Egyptians prepared to go out with Israel, for had God not shown His mighty power among them, attesting the reality of the redemption He had promised to His people? The real surprise would have been if none had responded in faith or wanted to go out with them.