I John 5:6-13 The Certainty Of God’s Witness.
It has always puzzled people as to what is meant by “water and blood.” A basic principle of interpretation, especially of difficult phrases like this, is to keep the context in mind-the immediate context of the passage in which a phrase like this is contained, but also the larger context of all the human author’s writings. One thing that stands out in the present context is that, the Spirit and the Father bear witness to “the water and blood” (Cf. 6b, 10b). So logically we should go to other passages that address the Father and the Spirit testifying to Jesus coming by water and blood. It is also true that the water, blood, and the Spirit are three separate witnesses, just as there are three who bear witness in heaven (vv. 7-8). John himself records Jesus’ conversation with Nicodemus where Jesus tells him that, unless one is born of water and the Spirit, he cannot enter the kingdom of God” (Jn. 3:5). So we see that physical birth is spoken of as being “born of water,” and it is certainly true that the Father and the Spirit bore witness to Jesus’ birth (Cf. Mt. 1:22-23; Lk. 1:35).
However, the Father and the Spirit also bore witness at Jesus water baptism just prior to his entering his public ministry (Mk. 1:10-11). We might also say that both the Father and the Spirit testified to the necessity of His death, and the shedding of his blood, as a witness to that blood sacrifice. “Others suggest that “water and blood” refers to the two sacraments, baptism and the Lord’s Supper” (NGSB pp. 1992-3). However, one must ask if this fits with the idea of Jesus coming by water and blood. Most of the explanations for “water and blood” don’t seem to take seriously the verb in this verse-namely that this is how Jesus came. However, we could also say in English that Jesus, “having come through water and blood” (v. 6). Put this way we could say that it could include everything through to the end of the gospel narratives. The other question is what does John mean by ‘through’, and it would seem logical to see this in light of the main activity of bearing witness. Though this is still not clear, verse 7 certainly is-the Trinity in heaven bears witness.
Whatever the water and blood are referring to, we at the very least know that they agree with the Trinity (v. 7), and all three agree together on earth (v. 8)-so there is two groups of three that all agree as one, and they agree in their testimony concerning Jesus, which John has again put forward here in this letter. When it comes to witness bearing, which had particular reference to capital crimes, according to the law there had to be 2 or three witnesses, and John seems to be saying that in the Trinity we have three witness who are each far superior to the witness of men (v. 9 Cf. Dt. 17:6; 19:15; Mt. 3:16-17; Jn. 5:31-34, 37; 8:14-18). He who does not believe this witness concerning the Son, does not have the Father or the Spirit either-because they are calling God a liar (v. 10). As John stated in his gospel, “He who has received His testimony has certified that God is true” (3:33). This testimony includes that we have eternal life in the Son (vv. 11-12). Assurance of these truths is why John wrote this epistle (vv. 13 Cf. Jn. 3:15-16; 6:47; 17:2-3; 20:31).