Midrasz do Wyjścia 12:18

God led them not by the way of the Philistines (ibid. 13:17). He guided them in the manner indicated in the verse Thou didst lead Thy people like a flock (Ps. 77:21), and as in the verse By day also He led them by a cloud (ibid. 78:14). By the way of the land of the Philistines, although that was near. The word near indicates that the promise the Holy One, blessed be He, had made to Abraham was soon to be fulfilled. Near also implies that it was the nearest way to return to Egypt. Furthermore near relates to the oath Abraham had sworn with Abimelech. Now therefore, swear unto me here by God, that thou wilt not deal falsely with me, or with my son, nor with my son’s son (Gen. 21:23) was near fulfillment, even though his grandson had not yet been born. Furthermore, near implies that the previous war was too recent to risk another.¹The “previous war” being the one referred to in the continuation of the verse: lest … the people repent when they see war (Exod. 17:1). A tradition exists that the descendants of Ephraim left Egypt before the designated time and 300,000 were killed. See Ginzberg, Legends, vol. 3:8–9. Only ten escaped. Another explanation of Although that was near. It was too close to the time in which the Canaanites had obtained the land, for it is written: And in the fourth generation they shall come back hither (ibid. 15:16), and the fourth generation had not yet come. God led the people about by the way of the wilderness (Exod. 12:18). The Holy One, blessed be He, said: If I lead them into the land by the most direct route, they will each take possession of a field and a vineyard and neglect the law. Therefore I will lead them through the wilderness for forty years and cause them to eat the manna and drink the water of the well so that the law may penetrate into their very beings.

4) This tells me only of the time that the Temple existed. Whence do I derive the same for these days, when the Temple does not exist (and there is no Paschal lamb)? From (Shemoth 12:18) "In the evening you shall eat matzoth."