1 John 5:6-8 (NKJV) This is He who came by water and blood—Jesus Christ; not only by water, but by water and blood. And it is the Spirit who bears witness, because the Spirit is truth. 7 For there are three that bear witness in heaven: the Father, the Word, and the Holy Spirit; and these three are one. 8 And there are three that bear witness on earth: the Spirit, the water, and the blood; and these three agree as one.
These verses are controversial with many interpretations and rejection of V7. Dr Wilbur Pickering writes on these:
His translation: “1 John 5:6-8 (WPNT) This is He who came by water and blood, Jesus Christ—not by the water only, but by the water and the blood. And it is the Spirit who bears witness, because the Spirit is the Truth; 7 actually there are three who bear witness 8 —the Spirit, the water and the blood—and the three are to one effect.”
His note: “Those who use the AV or NKJV are used to: “There are three that bear witness in heaven: the Father, the Word, and the Holy Spirit; and these three are one. And there are three that bear witness on earth: the Spirit, the water, and the blood; and these three agree as one.” The words in italics are only found in five late Greek manuscripts (less than 1% of the total) and part of the Latin tradition, from which they came. To be more precise, the manuscripts are: (61)[16th], (629)[14th], (918)[16th], 2318 [18th], 2473 [17th], wherein the cursives in ( ) all differ from each other; the two that agree verbatim with TR were probably copied from it. The only one that is clearly early enough to have served as TR’s exemplar, 629, is far too different—it lacks the seven last words in TR, omits another five, changes five and adds two—19 out of 40 words is too much; the Textus Receptus is not based on cursive 629, so it must be a translation from the Latin (or its exemplar is lost). The shorter reading makes excellent sense. [Those who make ‘the three heavenly witnesses’ a litmus test for orthodoxy are either ignorant or perverse (or both).]”
I give it a 50/50 possibility that V7 is correct.
My rendering and notes:
V6 This is the one who came through water and blood-Jesus Christ, not just in water only but in the water and the blood. The Spirit is bearing witness, because the Spirit is the truth.
William Kelly (William Kelly Major Works) comments on this verse:
Consequently the washing of water is from the riven side of Him that died for sinners. This enhances its force immensely. So before He died the Lord laid down, “He that is bathed (i.e., washed all over) needeth not save to wash his feet.” The person receives but one bathing; the feet need to be washed throughout the earthly pilgrimage. Christ’s advocacy is what really meets the daily failures, not the Lord’s Supper (a profane as well as an ignorant misuse of it); and the Holy Spirit applies His word on the ground of His death, whenever the need arises; but there is once only for the Christian “the washing of regeneration.” Nothing but the death of Christ gives us clearance from sin. We may indeed feel and hate the sin, and judge ourselves because of it; but there is no clearance of the soul apart from Christ’s death. “This is he that came,” etc. Such is the grand truth that was before God in Christ’s death. And Christ is here summed up for the testimony of God in His death. How deep the truth! How incomparable the grace which could so speak to us!
V7 There are three bearing witness in heaven, the Father, the Word, and the Holy Spirit, and these three are one.
Compare Prologue To The Canonical Epistles, Treatises 1 5:423, Liber Apologeticus, Cyprian of Carthage Treatise 1:6, and Varimadum 90:20-21.
V8 There are three bearing witness on earth, the spirit, the water, and the blood, and these three agree in one.
These are witnesses to the atoning work of the Lord Jesus Christ. Some understand the spirit to be the Holy Spirit who testified at Jesus’s baptism, while the water and blood testified to His true death on the Cross for the penalty of our sin when the soldier ran the spear into Jesus’s side (John 19:34).
V6 “This is He who came by water and blood—Jesus Christ; not only by water, but by water and blood. And it is the Spirit who bears witness, because the Spirit is truth.” Adam Clarke writes: “Jesus was attested to be the Son of God and promised Messiah by water, i.e. his baptism, when the Spirit of God came down from heaven upon him, and the voice from heaven said, This is my beloved Son, in whom I am well pleased. Jesus Christ came also by blood. He shed his blood for the sins of the world; and this was in accordance with all that the Jewish prophets had written concerning him. Here the apostle says that the Spirit witnesses this; that he came not by water only – being baptized, and baptizing men in his own name that they might be his followers and disciples; but by blood also – by his sacrificial death, without which the world could not be saved, and he could have had no disciples. As, therefore, the Spirit of God witnessed his being the Son of God at his baptism, and as the same Spirit in the prophets had witnessed that he should die a cruel, yet a sacrificial, death; he is said here to bear witness, because he is the Spirit of truth.”
V7 “For there are three that bear witness in heaven: the Father, the Word, and the Holy Spirit; and these three are one.”
V8 “And there are three that bear witness on earth: the Spirit, the water, and the blood; and these three agree as one.” Adam Clarke writes: “This verse is supposed to mean “the Spirit – in the word confirmed by miracles; the water – in baptism, wherein we are dedicated to the Son, (with the Father and the Holy Spirit), typifying his spotless purity, and the inward purifying of our nature; and the blood – represented in the Lord’s Supper, and applied to the consciences of believers: and all these harmoniously agree in the same testimony, that Jesus Christ is the Divine, the complete, the only Savior of the world.” – Mr. Wesley’s notes.”
We learn:
God the Father and God the Holy Spirit testified about Jesus