John, just as truly as Peter and James, ministered to the Circumcision, and referred to the nations as outside the sphere of fellowship (cf 3 Jn.7). Even when he widens the scope of blessing to include the whole world, he lays the heaviest stress on its relation to the favored nation. "He is the Propitiatory Shelter concerned with our sins (Israel's) yet not concerned with ours only, but concerned with the whole world also" (1Jn.2:2).
Furthermore, while our present grace is based on the repudiation of all privilege which comes through the flesh (2Co.5:16), since the nations have no physical connection with Christ, John commences his epistle by enforcing the physical evidence on which his ministry is founded. He knew Christ after the flesh for many years, and had rested in His bosom. This is the sphere into which he introduces us in his writings. In contrast to this, Paul never met Christ until He was glorified, and thus became the divine illustration of our relationship with Him.
The clue to the character and application of John's ministry, both personal and written, lies in the Lord's question to Peter (Jn.21:22) "If I should be wanting him to be remaining till I am coming, what is it to you ?" The Lord did not say that he actually would remain alive until His return, but we have little room to doubt that, in spirit, this is true. His writings have special application to those who enter the kingdom without dying, and provide the doctrinal basis of the kingdom itself. This is further confirmed by the fact that, in his apocalyptic visions, John enters the kingdom, in spirit.
And this is the reason why his writings have made such an appeal to the saints of today. During the kingdom, eon blessing will flow through Israel to the nations. So in John, we have God's love for the world (Jn.3:16). Christ's propitiation is worldwide in its scope. But never is there any hint anywhere of blessing for the nations during Israel's apostasy, as is the case in the Pauline epistles.
It is a fact but little realized that John's writings were not penned until after the death of Paul and Peter and most of the saints who come before us in the Scriptures. They all preached and taught without having ever seen the gospel or the epistles of John. Paul's marvelous ministries were not only carried out without these writings, but he followed lines of truth decidedly distinct from that of John's record. They are ours to read and interpret in their true setting, but not to apply to a time for which they are neither fitted nor intended. John's gospel and epistles were written too late to be used by most of the Circumcision in the past, hence have their special sphere and application in the future. John has not yet come to his own, and will have to tarry; for his fullest ministry till the Lord comes.
The subject of these epistles is life in the saints rather than life in Christ. This life manifests itself in conduct which must satisfy the severe tests applied for the exposure of a spurious spirituality. The professor is tested as to where he walks (1:6), his profession of sinlessness (1:8) and perfection (1:10), his knowledge of God (2:4), his remaining in Christ (2:6), his love of the brethren (2:9) and his love of God (4:20). John's "if we should say," is like James' test "If anyone should be saying." John sets God before the believer as Light, Love, and Spirit, while Paul sets the believer before God in Christ.
John's teaching approximates that of Hebrews in many respects. It puts Jesus Christ as an Entreater between the Father and His children as Hebrews puts the Son of God as Priest between God and believing Israelites.
John says very little about himself. In his gospel, there is only one John the Baptist. He speaks of himself as one whom Jesus loved (Jn.13:23, 21:20). A single page of Paul is more self-revealing than all John has written, and this picture of our pattern (1Ti.1:16) is given for our imitation.