Exodus 12:40-42 Rp. Time spent in Egypt. The Biblical writers are not in agreement about the length of Israel's stay in Egypt. Here it is given (probably by Rp) as 430 years (cf. 400 years in Genesis 15:13 Rje, Acts 7:6, and Josephus). But in Exodus 6:14-27 (also Rp, cf. Genesis 15:16 E) Moses and his contemporaries are the fourth generation. To reconcile the two estimates, the words and in the land of Canaan, i.e. before the entry into Egypt, are interpolated in Exodus 12:41 by LXX, Sam., reducing the time to twenty-five years. The fact is that neither the Bible nor the monuments enable us to solve the problem. Gressmann, however, argues that the sojourn of the Israelites in Egypt cannot well have lasted longer than one or two generations, because they still kept a clear memory of their homeland, and because their connexion with their brothers who remained in S. Palestine was not yet destroyed. But if some clans stayed in Canaan, or went back after the famine, their kinsfolk might keep in touch with them, since the inscriptions prove there was much coming and going across the desert.
Exodus 12:42. Render as mg. Further, the suggestion of Budde, based on Heb. idiom and Gr., and followed by Bacon, Nowack, Baentsch, and Driver, is attractive: A night of watching was it for Yahweh to bring them out, i.e. a night when He kept vigil to protect and deliver Israel. Then Exodus 12:42 b, implying a vigil kept year by year to Yahweh, must be by a later hand, and Exodus 12:42 a may be an early fragment of J following on Exodus 12:21-27.
Exodus 12:43-50 P. Supplementary Passover Rules. From the days of the mixed multitude and onwards difficulties arose about the status of non-Israelites, and the line was drawn differently and kept more or less strictly according to circumstances. In JE and D (cf. Exodus 22:21, Exodus 23:9; Deuteronomy 10:18 f., etc.) the stranger (gê r) better sojourner (Leviticus 17:8 f.*, Deuteronomy 1:16 *, p. 110) is inevitably in an inferior and dependent position. In P he has practical equality within his reach. So LXX already renders gê r by proselyte. But (Exodus 12:43) no alien (better foreigner) as such might even eat the Passover, i.e. share in the feast as a guest. If, however (Exodus 12:44), he were bought as a slave and circumcised, he was admissible. (A slave's son, as home-born, was admitted as a matter of course.) Yet (Exodus 12:45) a sojourner (rather settler, tô shâ b) and a hired servant were to be excluded. Perhaps this means that not only foreigners passing through, but even those settling and taking temporary service in, the land were excluded, it being presumed that they did not wish to be naturalised and to submit to circumcision. If, however (Exodus 12:48), a sojourner should sojourn with thee, and will do the passover to Yahweh, i.e. in his own right offer the Passover sacrifice (M-' Neile), or better celebrate the Passover feast (Baentsch, Driver), circumcision was the sole condition of admission. The Kikuyu controversy arose about the admission of members of other churches to communion while sojourning outside the borders of their own church. The Hebrew rule required virtual identification before admission to communion. Archbishop Davidson advised Anglicans to admit sojourners without confirmation. It seems precarious, with Driver, on etymological grounds to regard the settler as more permanently settled than an ordinary gê r. That the irrelevant section Exodus 12:46 f. separates the two passages about aliens suggests that they may have had an independent origin, which would account for the seeming conflict between Exodus 12:45 and Exodus 12:48. In the intervening verses four points are dealt with. Though small households might combine, the mystic unity of the group must be maintained: the lamb must be eaten in one house, and no part taken to a neighbour's across the road. So, too, no bone might be broken, or one part severed from another. And the observance was binding on all Israelites. (Cf. the Anglican rubric, Every parishioner shall communicate three times in the year, of which Easter shall be one.)
Exodus 12:51 is repeated by the Redactor of P from Exodus 12:41 to round off the section.