Shechakim , "expanses," with reference to the extent of heaven. (33:26; Job 35:5) St. Paul's expression "third heaven," (2 Corinthians 12:2) had led to much conjecture. Grotius said that the Jews divided the heaven into three parts, viz.,
The air or atmosphere, where clouds gather;
The firmament, in which the sun, moon and stars are fixed;
The upper heaven, the abode of God and his angels, the invisible realm of holiness and happiness the home of the children of God.