In the premiere episode, Icabod reads a passage from Washington's bible.  "I looked, and there before me was a white horse! Its rider held a bow, and he was given a crown, and was named Death, and Hell was following close behind him." He explains that this is referring to the Headless Horseman (who rides a white horse & has a bow shaped mark upon his hand) and that he is the first of the Four Horsemen of the Apocalypse.  Problem is, this is an inaccurate quote from the Book of Revalation.  In the actual text, the first seal does indeed reveal the first rider, upon a white horse, holding a bow & given a crown.  However, this rider is Conquest, not Death.  The rider Death is revealed with the breaking of the 4th seal (i.e., he is the 4th Horseman, not the 1st), riding a pale horse, does not carry a bow, and is the one that Hell follows.  The relevant texts are below...

"I watched as the Lamb opened the first of the seven seals. Then I heard one of the four living creatures say in a voice like thunder, 'Come and see!' I looked, and there before me was a white horse! Its rider held a bow, and he was given a crown, and he rode out as a conqueror bent on conquest."  Revalation 6:1-2

"When the Lamb opened the fourth seal, I heard the voice of the fourth living creature say, 'Come and see!' I looked and there before me was a pale horse! Its rider was named Death, and Hell was following close behind him. They were given power over a fourth of the earth to kill by sword, famine, and plague, and by the wild beasts of the earth."  Revalation 6:7-8