An angel is a spiritual being serving God, mainly as a messenger or guardian. Angels are celestial mediators between God and humanity. The Lord often sends them to earth to accomplish His Will, deliver a message, or protect and deliver His people. Where should we look for answers? The Word of God is the only source of spiritual truth. The spirit realm may not be visible to the natural eye, but it is as real as the natural world. Angels minister to the "heirs of salvation." In John 1:51, Jesus said, "Truly, truly, I tell you, you will all see heaven open and angels descending and ascending on the Son of Man." The Scriptures clearly show that God sends angels to minister on earth. A variety of activities and appearances are performed by angels.