If we say that we have fellowship with Him

1 John 1:6 
If we say that we have fellowship with him,.... 

The Alexandrian copy reads, "for if we say": that is, if any profess to be partakers of the divine nature, to be like unto God, and to have communion with him, to have the light of his countenance, and the discoveries of his love: and walk in darkness; in the darkness of sin, ignorance, and unbelief, or are in a state of unregeneracy and blindness; whose understandings are darkened, and they know not God in Christ, nor have any true sight and sense of themselves, their sin and danger; and are ignorant of Christ and his righteousness, and the way of salvation by him; and are strangers to the Spirit of God, and the work of his grace; and are unacquainted with the truths of the Gospel; and not only so, but go on in darkness more and more; prefer it to the light, love it, and the works of it; have fellowship with them, and choose them; take pleasure in the ways of sin and wickedness, and continue, and walk on in them; if such persons pretend to fellowship with God, they are liars: we lie; it cannot be, it is a contradiction, the thing is impossible and impracticable; what communion hath light with darkness? 
or what fellowship can the throne of iniquity, or those in whom sin reigns, have with God? for God is light, and were they partakers of him, or like unto him, or had communion with him, they would consequently be in the light, and not in darkness, and much less walk in it; wherefore they are liars, and do not the truth: they do not say the truth, nor act according to it; they do not act uprightly or sincerely, but are hypocrites, and pretend to that which they have not; and if they did the truth, they would come to the light, and not walk in darkness; 
see John_3:21.


John 3:21  But anyone working and living in truth and reality welcomes God-light so the work can be seen for the God-work it is."

Are that does truth - He who does right, or he that obeys the truth. Truth here is opposed to error and to evil. The sinner acts from falsehood and error. The good man acts according to truth. The sinner believes a lie - that God will not punish, or that there is no God, or that there is no eternity and no hell. The Christian believes all these, and acts as if they were true. This is the difference between a Christian and a sinner.
Cometh to the light - Loves the truth, and seeks it more and more. By prayer and searching the Scriptures he endeavors to ascertain the truth, and yield his mind to it.
May be made manifest - May be made clear or plain; or that it may be made plain that his deeds are performed in God. He searches for truth and light that he may have evidence that his actions are right.
Wrought in God - That they are performed according to the will of God, or perhaps by the assistance of God, and are such as God will approve. The actions of good people are performed by the influence and aid of God, Phi_2:12. Of course, if they are performed by his aid, they are such as he will approve. Here is presented the character of a good man and a sincere Christian. We learn respecting that character:
1. He does truth. He loves it, seeks it, follows it.
2. He comes to the light. He does not attempt to deceive himself or others.
3. He is willing to know himself, and aims to do it. He desires to know the true state of his heart before God.
4. A special object of his efforts is that his deeds may be “wrought in God.” He desires to be a good man; to receive continual aid from God, and to perform such actions as he will approve.
This is the close of our Lord’s discourse with Nicodemus - a discourse condensing the gospel, giving the most striking exhibition and illustration of truth, and representing especially the fundamental doctrine of regeneration and the evidence of the change. It is clear that the Saviour regarded this as lying at the foundation of religion. Without it we cannot possibly be saved. And now it becomes every reader, as in the presence of God, and in view of the judgment-seat of Christ, solemnly to ask himself whether he has experienced this change? whether he knows by experience what it is to be born of that Spirit? If he does he will be saved. If not, he is in the gall of bitterness and in the bond of iniquity, and should give no sleep to his eyes until he has made his peace with God.