Exodus 12:1

And the Lord spoke to Mosheh and to Aharon in the land of Mizraim, saying,

בארץ מצרים לאמר, seeing that this is a paragraph containing a great deal of legislation, it was important to state that this legislation was legislated when the Israelites were still in Egypt. The other commandments of the Torah were communicated to Moses/people either at Mount Sinai, the Tabernacle, or in the wilderness of Moav, shortly before Moses’ death. [there were also some at Marah, on the way to Mount Sinai. Ed.]

בארץ מצרים, “in the land of Egypt.” Outside of the capital. If a conversation with G–d concerning a minor matter required Moses to leave the capital, as we know from Exodus 9,29, when something of major importance was to be discussed this required him to leave the capital of Egypt even more so.[This is all based on the extraneous words “in the land,” in our verse. It would have otherwise sufficed to simply write: “in Egypt.” Ed.] The reason why outside the capital of Egypt G–d would address Moses was that the land of Israel had not yet been chosen as the only area from which prophecy would be received. [When the first Temple was destroyed the prophet Ezekiel did receive prophetic visions as we know from Ezekiel 3,22. So did the prophet Jonah (Jonah 1,3) who had fled from the Holy Land. At any rate, as long as Jerusalem had not become the capital of Israel, G–d sometimes addressed prophets outside its boundaries. During those years sacrificial offerings were also acceptable outside Jerusalem. Moses’ warning in Deuteronomy 12,13, not to offer such offerings any place the owner of the animal chose to do so, was also not effective before the Temple stood in Jerusalem. The town itself was potentially on a spiritual level where prophetic visions could be received. As long as Aaron had not been appointed as High Priest, any area was potentially fit to serve as sovereign soil for the Jewish people under a king. These rules are derived from verses in Kings I 8,16, as well as from Chronicles II 13,5.