In 1 John the subject of fellowship is the permeating theme throughout the book. John writes in 1:3 his reason for putting it all down, namely, that his audience can have fellowship with him and other believers -- and with God and His Son Jesus Christ. He is attempting to convey what he saw in the life of Christ and all that he experienced so that all who read this account can have the same fellowship. The fellowship that he speaks of is a fellowship with the Father and His Son Jesus Christ. This fellowship is something that John obviously sees as important, and the preservation of this epistle is evidence that the Holy Spirit has something to say to all who read the account.

In order to understand what John is speaking of when he says, "to have fellowship with us," a brief word study on "fellowship" is in order due to the nature of 1 John. Attempting to understand what fellowship means in this instance is the key to understanding what John is talking about.

Koinwniva is the Greek word for fellowship here, and according to TDNT, it is an association involving close mutual relations and involvement - ‘close association, fellowship.’ i{na kai; uJmei`" koinwnivan e[chte meqÆ hJmw`n ‘in order that you may have fellowship with us’ 1 John 1:3. In secular Greek fellowship means "common" in three ways: 1) in the sense of common ownership, property, ideas, etc., 2) in the sense of what concerns all, e.g., societies, monies, resolves, and 3) in the sense of what is of little value. A second line of use is for "fellows" and "participants."

In the OT and Judaism the general sense of common is found only a few times in Proverbs (e.g. 1:14; 15:23; 21:9; 25:24). Another sense has reference to what is in general or ordinary use as distinct from what is consecrated (though the LXX uses another word in such cases). Thus the rabbis use a particular word for working days, or for ordinary ground, money, or food, or for animals slaughtered for common use. Only in apocryphal works (e.g., 1 Macc. 1:47) and Josephus is the word koinoŒs used as an equivalent for this.

In the NT koinwniva occurs nine times in this form. In the first occurrence in 1 John 1:3 the word is used as a direct object, and in the second occurrence right after that it is the subject of the sentence. The first instance is John introducing fellowship, and the second instance is his definition of fellowship. The sense "to share in something" is what John is speaking of. It is the bond that unites Christians, and it begins with the Father and the Son by an abiding that commences here and is fulfilled hereafter (3:2, 24; 4:13). It issues in the family fellowship of believers (1:3, 7).

Also in the NT there is the meaning of "to give a share in something." This rare Greek meaning is fairly common in the NT. It is found in the reciprocal sharing of Phil. 4:15 and Gal. 6:6 (cf. 1 Cor. 9:11). Paul also has it in connection with the collection for the Jerusalem church, which gives a definite form to the fellowship between the two parts of Christianity (Gal. 2:9; Rom. 15:26). The collection has the significance of fellowship in service (2 Cor. 8:4) in a sincere and ready sharing (2 Cor. 9:13). Active sharing is also the point in Heb. 13:16.

BAGD gives at least four different definitions for koinwnia: 1) association, communion, fellowship, close relationship, 2) generosity, fellow-feeling, altruism, 3) abstract for concrete sign of fellowship, proof of brotherly unity, even gift, contribution, 4) participation, sharing in something in the deeds of others such as that found in Philemon 6. The all-encompassing meaning here for this Greek word is fellowship, and it is this fellowship that John desires for his readers.

As previously stated "fellowship" is one of the primary themes of John’s first epistle. Man’s life comes through faith in Jesus as the Son of God, and it consists in fellowship with God and with man. "Our fellowship" which is "the fellowship, that which is ours," is a phrase that is John’s practice of defining and emphasizing a noun by an article and possessive pronoun. Ours (possessive instead of personal pronoun) indicates fellowship as a distinguishing mark of Christians rather than as merely something enjoyed by them.

The fellowship has an object. In this instance it is "with the Father and with the Son." This is a purpose clause used with the present active subjunctive of ejcw ("that you may keep on having"). The people John is speaking of here are those who have not seen Jesus as well as those who, like John, have seen Him. There is a repeated preposition ("with") distinguishing the two persons and coordinating the fellowship with the Father, and the fellowship with the Son, thus implying sameness of essence. Having fellowship with both regards both as united in the Godhead. Plato says of one who lives in unrestrained desire and robbery, "Such an one is the friend neither of God nor man, for he is incapable of communion, and he who is incapable of communion (fellowship) is also incapable of friendship." So, in the "Symposium," he defines divination "the art of communion (fellowship) between gods and men" (Vincent's Word Studies of the New Testament). The careful explanation of the word "fellowship" (partnership), involves fellowship with the Father and with his Son Jesus Christ, but it is only possible through Christ Jesus Himself (Robertson's Word Pictures in the New Testament).

Fellowship in 1 John means companionship. It is a relation in which parties hold something in common -- in this case the Father and the Son. Christians have fellowship with the Father and the Son and the Holy Spirit, as seen in 2 Corinthians 13:14, as well as with one another (1 John 1:7). As pertains to men, no one can know God and be in fellowship with Him unless he obeys God (2:3-6) and has love (Romans 8:38-39). As Unger has said, "The fellowship of believers embraces confession of sins one to another with prayer (James 5:16); assembly, with exhortation and stimulation to love and good works (Heb. 10:24-25); partaking of the Lord's Supper (1 Cor. 11:24-25); ‘contributing to the needs of the saints’ (Rom. 12:13; 15:25; Acts 11:29; 1 Cor. 16:1-2; 2 Cor. 8:4; Heb. 13:16); bearing the infirmities of the weak; and pleasing one’s neighbor (Rom. 15:1-2). Love for and fellowship with one another are necessary to, and an evidence of, fellowship with God (1 John 4:12). Even Christ prayed that His people might have fellowship with each other (John 17:21)." In this case it can be seen that fellowship with God and with Jesus is essential to a personal relationship with Christ resulting in fruitful living. It is no wonder that John writes his epistle with fellowship as the underlying theme. The fact that he writes about it so passionately should spur the reader on to greater fellowship with the Almighty God and His Son Jesus Christ.