The physical world exists because of the spiritual life force within it. This spiritual life force emanates from God through a spiritual hierarchy until it reaches the physical world. Ya’akov Avinu was part of this spiritual hierarchy. Ya’akov Avinu was therefore the vehicle through which the spiritual life force that was responsible for the continuing existence of Egypt and the Egyptians descended. This is why the parsha starts with the words “ויחי יעקב בארץ מצרים/Ya’akov lived in the land of Egypt …” (Breishis 47:28) instead of the more usual “וישב יעקב .../Ya’akov dwelt.” ויחי/He lived suggests that he also gave life to the land of Egypt. Ya’akov compared himself to God as a creator of worlds in the sense that he gave life to Egypt.
Why, though, did God use Ya’akov as the mechanism for giving life and existence to Egypt? A Zohar2 in parshas VaYeishev gives us a clue. The Zohar says that the redemption from Egypt could only have happened because the brothers treated Yosef like a slave. What is the connection between the redemption and the way that Yosef’s brothers treated him? Since the relationship between the brothers and Yosef was one of masters to a slave – they sold him – and Yosef ruled over the Egyptians, it follows that the brothers were also rulers over the Egyptians. The fact that we were slaves to the Egyptians for a period of time was a temporary anomaly which was corrected with our redemption from Egypt. If the brothers had not sold Yosef, had not treated him as a slave, and we had subsequently gone to Egypt, we would not have been redeemed from Egypt, according to the Zohar. This Zohar is teaching us that for redemption to occur, the seeds of redemption must have been planted before the exile.
This concept explains our Midrash as well. God used Ya’akov as the vehicle for imparting life to Egypt in order to subordinate Egypt to Ya’akov. This was another seed of the redemption which God planted before the exile. It made the redemption possible. Ya'akov wanted to encourage his children on the eve of the exile. He therefore explained to them that the seeds of the redemption were already at hand.