I'm not familiar with the white horse in the Bible, unless you Revelations, But white horses are usually a symbol of purity.
 As Pestilence
The other three horsemen represent evil, destructive forces, and given the unified way in which all four are introduced and described, it may be most unlikely that the first horseman is correspondingly evil. The rider of white horse is often associated with Plague, as the bow is the symbol of Apollo and Artemis, and in Greek stories, illness was thought to be caused by their arrows. The German Stuttgarter Erklärungsbibel casts him as civil war and internal strife. One interpretation—which was held by evangelist Billy Graham—casts the rider of the white horse as the Antichrist, or a representation of false prophets, citing differences between the white horse in Revelation 6 and Jesus on the white Horse in Revelation 19. In Revelation 19 Jesus has many crowns, but in Revelation 6 the rider has just one.
Rev. 6:2 is the scripture. However, throughout the bible, horses represent warfare. The one in Rev. gleams with whiteness, indicating unblemished holiness, portraying warfare that is clean and righteous in God's eyes. The rider is Jesus Christ!
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