Regardless of what you may believe, parts of the bible are incredibly fascinating, including the four horsemen, which are described in the last book of the New Testament (thanks, Wikipedia!). Wiki goes on to say:
The chapter tells of a “‘book’/'scroll’ in God’s right hand that is sealed with seven seals”. The Lamb of God/Lion of Judah (Jesus Christ) opens the first four of the seven seals, which summons forth four beings that ride out on white, red, black, and pale horses. Although some interpretations differ, the four riders are commonly seen as symbolizing Conquest, War, Famine and Death, respectively. The Christian apocalyptic vision is that the four horsemen are to set a divine apocalypse upon the world as harbingers of the Last Judgment.
Pretty cool/frightening, eh? We’ll keep showing you the progression of this tattoo. Here’s phase one!