For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
John wrote the following books
gospel of John,
1John,
2John,
3John, and
Revelation(Rev. 1:9).
► More information about Apostle John:
✿ John was a disciple, Apostle, prophet
✿ John the most beloved disciple among the 12(Jn. 13:23; 19:26; 20:2; 21:7,20,24).
✿ An apostle and brother of James (Mt. 4:21).
✿ Present with James and Peter on several occasions (Mk. 5:37; 9:2; 14:33).
✿ Intolerance of (Mk. 9:38; Lk. 9:49-56).
✿ Prepares passover (Lk. 22:8-13).
✿ Present at the trial (Jn. 18:15-16; 19:26-27),
✿ at the tomb (Jn. 20:2-8), and
✿ on other occasions (Jn. 21).
✿ Received Spirit baptism (Acts 1:13--Acts 2:11).
✿ Entrusted with Mary (Jn. 19:26).
✿ With Peter in the temple (Acts 3).
✿ In jail (Acts 4-5).
✿ Sent to Samaria (Acts 8:14-17).
✿ Was a pillar in the church (Gal. 2:9).
✿ He is believed to have died a natural death at the age of 100.
Unbroken tradition affirms between statements of 1 John and the gospel of John that they had the same author:
1J1 Jn 2:8 h Jn 1:5, 9; 13:34;
1 Jn 2:10 ith Jn 11:10;
1 Jn 2:13 ith Jn 17:3;
1 Jn 2:14 ith Jn 17:3;
1 Jn 3:1 ith Jn 1:12;
1 Jn 3:2 ith Jn 1:12;
1 Jn 3:2 ith Jn 17:24;
1 Jn 3:8 ith Jn 8:44;
1 Jn 3:8-9 ith Jn 3:3-5
1 Jn 3:11 ith Jn 13:34;
1 Jn 3:13 ith Jn 15:20;
1 Jn 4:9 ith Jn 3:16;
1 Jn 4:12 ith Jn 1:18;
1 Jn 5:13 ith Jn 20:31;
1 Jn 5:14 ith Jn 14:14;
1 Jn 5:20 ith Jn 17:2-3.