Heaven. There are four Hebrew words thus rendered in the Old Testament. 1. Râkî'a, A. V. firmament. 2. Shâmayim; used in the expression, "the heaven and the earth," or "the upper and lower regions." Genesis 1:1. 3. Mârôm, used for heaven in Psalms 18:16; Isaiah 24:18; Jeremiah 25:30. Properly speaking, it means a mountain, as in Psalms 102:19; Ezekiel 17:23. 4. Skechâkîm, "expanses," with reference to the extent of heaven. Deuteronomy 33:26; Job 35:5. Paul's expression, "third heaven," 2 Corinthians 12:2, has led to much conjecture. Grotius said that the Jews divided the heaven into three parts, viz., 1. The air or atmosphere, where clouds gather. 2. The firmament, in which the sun, moon, and stars are fixed. 3. The upper heaven, the abode of God and his angels.