Joseph’s burial was unique. He was buried in an aron, or casket. He is the first person recorded in the Bible to be buried in such a manner. While nowadays this is commonplace, in the US at least, that was not the case in antiquity. People were generally buried directly in the ground, or in caves.
The Bechor Shor explains that Joseph wanted to be buried in a casket so that his remains could easily be transported back to the land of Israel for interment. Had he been buried directly in the ground, his remains could have deteriorated, or the location of his burial could have been forgotten. Either scenario would have made it very difficult to transport his remains to Israel many years later.
Where was the casket placed in Egypt? The Seforno writes that Joseph’s casket was kept above ground for all the years that the Jewish people were enslaved in Egypt. Its location needed to be well known to the people so that they could take it with them when they left Egypt. The Rashbam disagreed with this approach (though he lived 400 years before the Seforno). According to the Rashbam, the casket was buried in the ground, perhaps as we do nowadays. The reason then that his body was placed in a casket was so that when the time came to leave Egypt, it would be easy to remove the casket from the ground, rather than have to remove Joseph’s decayed remains from the Earth.
For both the Seforno and the Rashbam, the casket served a very practical need of allowing Joseph’s remains to be identifiable and accessible for the journey back to the Land of Israel.
The Bechor Shor adds another piece of information which could provide additional meaning to the need for the aron, and explains why it is a fitting close to the book of Genesis.
The Bechor Shor quotes from the Midrash that Joseph’s body was not the only one carried out of Egypt after the long exile. All of Joseph’s brothers were ultimately buried in the Land of Israel. Each tribe took the remains of their own Patriarch as they left Egypt. The only exception was Joseph’s own tribes, Ephrayim and Menashe, since the Torah tells us (Exodus 13:19) that Moshe himself took the remains of Joseph out of Egypt. The Midrash bases this tradition on the Hebrew word ‘eitchem,’ with you, in the verse. Joseph tells his brothers, “my body will be transported with your bodies back to Egypt.”
Why then does the Torah not explicitly record anything about the burial of the brothers and their transport to the Land of Israel? The Bechor Shor writes that Joseph was worried that since Egypt would give him such a formal and honorable burial, perhaps the Jewish people would be hesitant to disinter his remains. Perhaps the Jewish people would say that of course the other patriarchs needed to be buried in the Land of Israel, but since Joseph had such a dignified funeral in Egypt that there was no reason to bring him back. Therefore, as the book of Genesis comes to a close, Joseph reminds his brothers, and us, the readers of the Torah, that despite any honor and fanfare received in the exile, a Jew’s place is always in the Land of Israel. Joseph’s fate is tied to that of his true brothers, who will be transported back to Israel, and not with the people of Egypt. The aron served as a reminded that one is not truly at rest until one reaches Israel.