That which was from the beginning, which we have heard, which we have seen with our eyes, which we have looked upon, and our hands have handled, of the Word of life;
That which was — Here means, He which was the Word himself; afterwards it means, that which they had heard from him.
Which was — Namely, with the Father, verse 2, before he was manifested.
From the beginning — This phrase is sometimes used in a limited sense; but here it properly means from eternity, being equivalent with, "in the beginning," John 1:1.
That which we — The apostles. Have not only heard, but seen with our eyes, which we have beheld - Attentively considered on various occasions.
Of the Word of life — He is termed the Word, John 1:4; as he is the living Word of God, who, with the Father and the Spirit, is the fountain of life to all creatures, particularly of spiritual and eternal life.
 (For the life was manifested, and we have seen it, and bear witness, and shew unto you that eternal life, which was with the Father, and was manifested unto us;)
For the life — The living Word.
Was manifested — In the flesh, to our very senses.
And we testify and declare — We testify by declaring, by preaching, and writing, 1 John 1:5-10: writing builds there on.
To you — Who have not seen.
The eternal life — Which always was, and afterward appeared to us. This is mentioned in the beginning of the epistle. In the end of it is mentioned the same eternal life, which we shall always enjoy.
 That which we have seen and heard declare we unto you, that ye also may have fellowship with us: and truly our fellowship is with the Father, and with his Son Jesus Christ.
That which we have seen and heard — Of him and from him.
Declare we to you — For this end.
That ye also may have fellowship with us — May enjoy the same fellowship which we enjoy.
And truly our fellowship — Whereby he is in us and we in him.
Is with the Father and with the son — Of the Holy Ghost he speaks afterwards.
 And these things write we unto you, that your joy may be full.
That your joy may be full — So our Lord also, 16:22. There is a joy of hope, a joy of faith, and a joy of love. Here the joy of faith is directly intended. It is a concise expression.
Your joy — That is, your faith and the joy arising from it: but it likewise implies the joy of hope and love.
 This then is the message which we have heard of him, and declare unto you, that God is light, and in him is no darkness at all.
And this is the sum of the message which we have heard of him - The Son of God.
That God is light — The light of wisdom, love, holiness, glory. What light is to the natural eye, that God is to the spiritual eye.
And in him is no darkness at all — No contrary principle. He is pure, unmixed light.
 If we say that we have fellowship with him, and walk in darkness, we lie, and do not the truth:
If we say — Either with our tongue, or in our heart, if we endeavour to persuade either ourselves or others. We have fellowship with him, while we walk, either inwardly or outwardly, in darkness - In sin of any kind.
We do not the truth — Our actions prove, that the truth is not in us.
 But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.
But if we walk in the light — In all holiness. As God is (a deeper word than walk, and more worthy of God) in the light, then we may truly say, we have fellowship one with another - We who have seen, and you who have not seen, do alike enjoy that fellowship with God. The imitation of God being the only sure proof of our having fellowship with him.
And the blood of Jesus Christ his Son — With the grace purchased thereby.
Cleanseth us from all sin — Both original and actual, taking away all the guilt and all the power.
 If we say that we have no sin, we deceive ourselves, and the truth is not in us.
If we say — Any child of man, before his blood has cleansed us.
We have no sin — To be cleansed from, instead of confessing our sins, 1 John 1:9, the truth is not in us - Neither in our mouth nor in our heart.
 If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.
But if with a penitent and believing heart, we confess our sins, he is faithful - Because he had promised this blessing, by the unanimous voice of all his prophets.
Just — Surely then he will punish: no; for this very reason he will pardon. This may seem strange; but upon the evangelical principle of atonement and redemption, it is undoubtedly true; because, when the debt is paid, or the purchase made, it is the part of equity to cancel the bond, and consign over the purchased possession.
Both to forgive us our sins — To take away all the guilt of them.
And to cleanse us from all unrighteousness — To purify our souls from every kind and every degree of it.
 If we say that we have not sinned, we make him a liar, and his word is not in us.
Yet still we are to retain, even to our lives' end, a deep sense of our past sins. Still if we say, we have not sinned, we make him a liar - Who saith, all have sinned.
And his word is not in us — We do not receive it; we give it no place in our hearts.