The hue of that portion of the visible spectrum between green and indigo with wavelengths between 420 – 490. Azure, cerulean, and sky-blue sapphire gemstones. Spiritually the color is symbolic of Heaven, Spiritual Authority, Revelation of the Holy Spirit, Integrity, Set apart for God’s purposes, Justice, Heavenly Character, Wealth, Holy Covering, Loyalty, Divinity, Revelation Knowledge, Grace, Mercy, Royalty, Priesthood. Blue is the 5th Stone on the Priest’s Ephod: Sapphire which symbolizes the Tribe of Simeon. The word Simeon means to hear God. Blue is also symbolic of the 2nd Gate.
A sampling of Biblical scriptures: Genesis 1; Exodus 22, 28:3, 39:8; Numbers 4:6, 15:37-41; 2 Chronicles 3:14; Esther 8:15; Isaiah 8:7; Jeremiah 46:7-8; Revelation 21, 22.