בא

During the Exodus, Moses did not forget Joseph’s request that his coffin be taken out of Egypt. The Sages describe the manner in which the coffin accompanied the people of Israel during their wanderings in the wilderness. 

The Sages taught: Come and see how beloved mitzvot were to Moses our teacher. As while all the Jewish people were involved in taking the plunder from the Egyptians, he was involved in mitzvot by taking Joseph’s coffin…. From where did Moses our teacher know where Joseph was buried? They said: Serah daughter of Asher remained alive from Joseph’s generation. Moses went to her and said to her: Do you know anything about where Joseph is buried? She said to him: The Egyptians fashioned a metal casket for him and set it in the Nile River so that its water would be blessed. And all those years that the Israelites were in the wilderness, there were these two chests – one containing the corpse of Joseph and one the Ark of the Divine Presence, traveling with each other. Passersby would say: What is the nature of these two chests? The Israelites would say: One is of a corpse and one is of the Divine Presence. They would ask: And is it the manner of a corpse to travel with the Divine Presence? The Israelites said: This person, Joseph, fulfilled everything that is written in the tablets in that ark.  <source>(<i>Sota</i> 13a) </source>