And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years, Genesis 6:3. The King James Bible in its 7th purification on this earth (The Cambridge Text as it stood from WWI to 1985), uses capitalizations, or the lack thereof to keep the Godhead more visible and understandable. It will be common in the Old Testament for the text to underline the role of the 2nd person in the Godhead as the creator by using a lower case "s".
By his spirit he hath garnished the heavens; his hand hath formed the crooked serpent, Job 26:13. That verse is the perfect companion verse to Ephesians 3:9, And to make all men see what is the fellowship of the mystery, which from the beginning of the world hath been hid in God, who created all things by Jesus Christ. Jesus Christ is the creator, therefore the spirit of the creator is designated with a lower case "s". When God wanted to teach Bezaleel the son of Uri to create, he gave him a lower case spirit. And I have filled him with the spirit of God, in wisdom, and in understanding, and in knowledge, and in all manner of workmanship, Exodus 31:3.
It is a recurring theme in my blog posts that same spirit that caused boneheaded Baptists (I am a Baptist) to attack the scriptures in Genesis 6:3 in 1848-50 (see part I) is back at it again. It is not the Spirit of God leading these men to obfuscate scripture. I John 5:6-8 were meant to be an outline of how the three designations for God's spiritual working, work together in harmony to prove that Jesus is the Son of God. This is he that came by water and blood, even Jesus Christ; not by water only, but by water and blood. And it is the Spirit that beareth witness, because the Spirit is truth. For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one. And there are three that bear witness in earth, the spirit, and the water, and the blood: and these three agree in one.
Verse 6 tells us that the inward witness of the Spirit (always a capital) bears witness. Verse 7 tells us that the actual third person of the Godhead bears witness (always designated the Holy Ghost). Verse 8 tells us that the the small "s" spirit of Jehovah God was released from an earthen vessel hanging on the cross. Three things came out of him and convinced the centurion that Jesus was the Son of God. The water, the blood and the spirit bear witness that Jesus is the Son of God. Boneheaded Baptists now have that under attack. Capitalizations do matter.