'Forty Days' in the Bible

For after seven days I will send rain on the earth for forty days and forty nights, for the destruction of every living thing which I have made on the face of the earth.

And rain came down on the earth for forty days and forty nights.

And for forty days the waters were over all the earth; and the waters were increased so that the ark was lifted up high over the earth.

Then, after forty days, through the open window of the ark which he had made,

And the forty days needed for making the body ready went by: and there was weeping for him among the Egyptians for seventy days.