Still another opportunity was given to Adam to learn and appreciate the value of the Sabbath. The celestial light, whereby Adam could survey the world from end to end, should properly have been made to disappear immediately after his sin. But out of consideration for the Sabbath, God had let this light continue to shine, and the angels, at sundown on the sixth day, intoned a song of praise and thanksgiving to God, for the radiant light shining through the night. Only with the going out of the Sabbath day the celestial light ceased, to the consternation of Adam, who feared that the serpent would attack him in the dark. But God illumined his understanding, and he learned to rub two stones against each other and produce light for his needs.