And the LORD spake unto Moses and Aaron in the land of Egypt, saying,
The Lord spake - rather, had spoken unto Moses and Aaron; for it is evident that the communication here described must have been made to them some time previous to the tenth of the month. Moses, writing the history of the events which preceded and accompanied the Exodus, seems to have inserted this parenthetical section, with all its minute details, because the express purpose of letting future generations of Israel know that the national institution of the Passover was not the legislative device of a subsequent period, but was enacted, with all its specialties, by divine authority before, and with reference to, the great catastrophe which led to the emancipation of the Hebrews.