Genesis 50:3

taking the forty days required to complete the embalming. And the Egyptians mourned for him seventy days.

And forty days were fulfilled for him; for so are fulfilled the days of those which are embalmed: and the Egyptians mourned for him threescore and ten days.

Note mourned: Heb. wept

Forty days were used for him, for that is how many days it takes to embalm. The Egyptians wept for Israel for seventy days.

And forty days were fulfilled for him; for so are fulfilled the days of embalming: and the Egyptians wept for him threescore and ten days.