Ya’akov tells his children to get ready to be dependent on the Non-Jews in the time of famine and that this is how God’s miracle would reach them, because he senses that Golus is coming. In Golus we get our food and knowledge (from Hashem, but) through the non-Jew. This is the meaning of ‘Lama Tisrau’, Ya’akov’s moment to the beginning of the Golus.