The Witness of Heavenly Father:

When the Jews persecuted Jesus for healing on the Sabbath Jesus pointed them to the testimony of Heavenly Father, the testimony of Old Testament scripture:

John 5:27-29  “And the Father himself, which hath sent me, hath borne witness of me.  Ye have neither heard his voice at any time, nor seen his shape.  And ye have not his word abiding in you: for whom he hath sent, him ye believe not.  Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me”.

The Witness of the Holy Ghost:

The Holy Spirit bears witness in the New Testament that throughout his ministry Jesus continually quoted scripture to backup his message as in Matthew 12:7:  “But if ye had known what this meaneth, I will have mercy, and not sacrifice, ye would not have condemned the guiltless”.  But this witness goes farther, makes the point stronger.  The Holy Spirit records how Jesus told the Jews he  doesn’t accuse them of their unbelief, because the truth of scripture  already accuses them:

John 5:45-47  “Do not think that I will accuse you to the Father: there is one that accuseth you, even Moses, in whom ye trust. ⁴⁶For had ye believed Moses, ye would have believed me: for he wrote of me. ⁴⁷But if ye believe not his writings, how shall ye believe my words?”.