In the Mosaic law, at least two reliable witnesses were required to convict a man of a crime. Jesus Christ was charged with blasphemy, claiming to be the unique Son of God. Not only was there the required double witness, but actually a fourfold witness to the "crime." The witnesses not only agreed that the claim was made, but also that the claim was true!
The first was John the Baptist, who said "I saw, and bare record that this is the Son of God" (John 1:34). To so testify was John’s very reason for being, for he "was sent to bear witness of that Light. That was the true Light" (John 1:8-9).
There was also a second, more potent witness. "I have greater witness than that of John," Jesus said, "for the works which the Father hath given me to finish, the same works that I do, bear witness of me, that the Father hath sent me" (John 5:36). The great teacher, Nicodemus, had to acknowledge, "No man can do these miracles that thou doest, except God be with him" (John 3:2).
Furthermore, there was the direct testimony of God from heaven. "The Father himself, which hath sent me, hath borne witness of me" (John 5:37). "There came such a voice to him from the excellent glory, This is my beloved Son, in whom I am well pleased" (2 Peter 1:17).
Most importantly, there is the testimony of the Bible. "Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me" (John 5:39).
We no longer have such direct testimony, but we will always have the Holy Scriptures, eternally proclaiming the deity of our Lord Jesus Christ. HMM