From Association of Independent Readers and Rootworkers
Hoodoo psychic readers, spirit workers and root doctors who recite Psalms on behalf of clients may work with Psalm 100 during
altar work and prayers to overcome enemies. Psalm 100 is used by root doctors to reverse evil back unto enemies and to bring about their defeat. This Psalm can be used to bring victory to any one facing dangerous enemies. Unlike imprecatory Psalms, Psalm 100 brings about the defeat of enemies by uplifting the client and helping them achieve the destruction of opponents. This Psalm can be used to bring victory.
 Make a joyful noise unto the LORD, all ye lands.
 Serve the LORD with gladness: come before his presence with singing.
 Know ye that the LORD he is God: it is he that hath made us, and not we ourselves; we are his people, and the sheep of his pasture.
 Enter into his gates with thanksgiving, and into his courts with praise: be thankful unto him, and bless his name.
 For the LORD is good; his mercy is everlasting; and his truth endureth to all generations.