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. (1 John 5:6)
Today’s big question: what does “the Spirit is truth” mean?
The Holy Spirit is called “the Spirit of truth” a few times in the books of John and 1 John, but today’s passage is a little different in that it states “the Spirit is truth.” We can learn about the authority of the Holy Spirit from this verse, and it also is consistent with the theology of the Trinity.
The first part of this verse references the sacrifice that Jesus Christ made in order to save mankind. We have learned in previous devotionals that the Spirit is also vital to the doctrine of salvation. The Spirit’s role in salvation, in light of this verse, can be further explained in Paul’s first epistle to the Corinthians:
But God has revealed them to us through His Spirit. For the Spirit searches all things, yes, the deep things of God. (1 Corinthians 2:10)
Paul told the Corinthians that God reveals truth to us through His Spirit, particularly the mystery of Christ’s work on the Cross. Paul also stated that the Spirit knows all things, as God knows all things. In Acts, we read that when Ananias lied to the Holy Spirit, he was guilty of lying to God (Acts 5:3–4).
We can easily conclude with these passages that the Spirit is God. So when we read that “the Spirit is truth,” this should come as no surprise. Since the Spirit is truth, He is our absolute authority in every area. Jesus said the following about the Spirit of truth:
“However, when He, the Spirit of truth, has come, He will guide you into all truth; for He will not speak on His own authority, but whatever He hears He will speak; and He will tell you things to come.” (John 16:13)
We should continually look to the Spirit to reveal truth as we read Scripture, as we are all fallible human beings that rely on our own philosophies and bias at times, rather than the truth of God’s Word. We should also consider the amazing concept that believers actually have the Truth—the Spirit—dwelling within them (1 Corinthians 6:19). http://www.answersingenesis.org/articles/2010/10/01/spread-the-gospel