Introduction to JohnChapters
The apostle and evangelist, John, seems to have been the youngest of the twelve. He was especially favoured with our Lord's regard and confidence, so as to be spoken of as the disciple whom Jesus loved. He was very sincerely attached to his Master. He exercised his ministry at Jerusalem with much success, and outlived the destruction of that city, agreeably to Christ's prediction, ch. 21:22. History relates that after the death of Christ's mother, John resided chiefly at Ephesus. Towards the close of Domitian's reign he was banished to the isle of Patmos, where he wrote his Revelation. On the accession of Nerva, he was set at liberty, and returned to Ephesus, where it is thought he wrote his Gospel and Epistles, about A. D. 97, and died soon after. The design of this Gospel appears to be to convey to the Christian world, just notions of the real nature, office, and character of that Divine Teacher, who came to instruct and to redeem mankind. For this purpose, John was directed to select for his narrative, those passages of our Saviour's life, which most clearly displayed his Divine power and authority; and those of his discourses, in which he spake most plainly of his own nature, and of the power of his death, as an atonement for the sins of the world. By omitting, or only briefly mentioning, the events recorded by the other evangelists, John gave testimony that their narratives are true, and left room for the doctrinal statements already mentioned, and for particulars omitted in the other Gospels, many of which are exceedingly important.
-- taken from Matthew Henry's Concise Commentary