In 1791 John Wesley was almost 90 years old. He was nearly blind, could hardly write and his memory was failing him:
In mid-February, he caught a cold, and on Sunday the 20th was unable to preach. He improved enough to preach the following Wednesday, the day of his last diary entry. That day, he also finished reading Gustavus Vasa, the life of a former Barbados slave, Olaudah Equiano. This book inspired Wesley to write, the following day, a word of encouragement to William Wilberforce, member of Parliament, in his fight against the slave trade: “Go on, in the name of God and in the power of his might, till even American slavery (the vilest that ever saw the sun) shall vanish away before it” (JWL, 8:265). Quoted in Wesley and the People Called Methodists , p. 307.
Wesley died less then two weeks later, on March 2, 1791.