Around 98 CE Jehovah's holy spirit moved the Apostle John to pen 3 letters to the disciples. His purpose was to motivate loyal Christians to maintain their faith and to keep on walking in the truth. Many false Christs had risen, and the apostasy was advancing, so John was worried what effect these false teachers, these antichrists were having on the congregations. His letters are in God's inspired Word for us to take advantage of today, to strengthen our faith, so that we too can keep on walking with the true God.