31 “If I bear witness of Myself, My witness is not true. 32 There is another who bears witness of Me, and I know that the witness which He witnesses of Me is true.
Jesus set forth His case for His deity in verses 17-30. In 5:31 to 47 He offered four witnesses to His right to offer eternal life to those who would believe. The issue is He is who He claimed to be. Jesus continues the argument of the essential unity between Him and the Father.
The remainder of the discourse is also a rebuke of unbelief for the Jew’s rejection of Jesus’ oneness with the Father. Jesus continues to answer the accusation against Him that He committed blasphemy by claiming that He was equal with God.
“If I [emphatic] bear witness of Myself, My witness is not true [valid].
Jesus did not need to express personal validation of His deity but He gave evidence of who He is to those who would join Him in His claims. Words for testifying or witness occur ten times in the following verses.
Testimony about oneself was not sufficient with the Jewish authorities because the biblical standard was to validate something by more than one witness in a legal situation (Dt 17:6; 19:15). They would be highly suspicious of Jesus making the kind of claim He did. Thus, Jesus conceded that Jewish law required more than one witness. Jesus did not say that His statements were not true to fact but that they were not true in the minds of His hearers should there be only one witness to a situation.
Jesus will give four witnesses to His deity. The situation Jesus faced was that it required independent confirmation of His deity.
There is another [of the same kind] who bears witness of Me,
The “another” here is the Father, a fully qualified witness (Jn 5:36-37; 1 Jn 5:9). Jesus is of the same kind as the Father. Jesus’ witness was not simply His witness but it is the witness of the Father as well. That witness is external to Himself.
and I know that the witness which He witnesses of Me is true [valid].
The Father witnessed to the authenticity of Jesus. Jesus did not speak merely of His own accord. Jesus’ knowledge came from His unity with the Father.
Corroboration of truth is important.
Corroborative witness within Scripture is essential to understand the whole counsel of God. We must disavow personal opinion based on our own approach to truth. As Jesus was not the sole source of His authority so we cannot rest on single substantiation of what we believe.