John Calvin Commentary Genesis 47:30

"but when I sleep with my fathers, thou shalt carry me out of Egypt, and bury me in their burying-place. And he said, I will do as thou hast said." — Genesis 47:30 (ASV)

But I will lie with my fathers. It appears from this passage that the word “sleep,” whenever it is used for “die,” does not refer to the soul, but to the body. For why did it concern him to be buried with his fathers in the double cave, unless it was to testify that he was associated with them after death? And by what bond were he and they joined together, except this: that not even death itself could extinguish the power of their faith, which would seem to utter this voice from the same tomb: Now we also have a common inheritance.