God’s Testimony: God has given undeniable testimony that Jesus is His Son. John points out three ways the Father attested to this. He declared it with His own voice at Jesus’ water baptism (Matt. 3:17).[1] He gave signs and wonders at the cross where Jesus gave up His lifeblood[2] to confirm His divine identity (Matt. 27:54).[3] Furthermore, the Father confirmed Jesus’ divinity through the miraculous works (“signs”) of the Spirit which He gave Him to perform.[4] This is the threefold testimony which the Father gave regarding His Son.
Unbelief: Everyone who believes this testimony overcomes the world. The world is being swept away by the Devil’s deception. There is only one truth that will rescue those under His sway and open their eyes to see spiritual reality: faith in Christ. This is the “red pill” that unveils the truth about everything: the world, its origins, good and evil, Satan, the Savior, redemption, and the kingdom of God. God has given an overwhelming testimony about His incarnate Son. To distrust His word and maintain unbelief is skepticism of the worst kind. It is to treat God as lesser than human witnesses whose words we accept in the court of law (5:9). Unbelief is to condemn God as a liar (5:10). This is spiritual suicide. It is to condemn the water grid as polluted, refuse to drink, and thus die of thirst. He who rejects God’s testimony ruins himself.
[1] God also declared it at His transfiguration, though it was not publicly heard (as it was His baptism) but only by Peter, James, and John (Matt. 17:1, 5; 2 Pet. 1:17-18).
[2] In the New Testament, blood is the word of choice for Jesus’ substitutionary death for sinners (cf. Matt. 26:28; Acts 20:28; Rom. 3:25; 5:9; Eph. 1:7; 2:13; Col. 1:20; Heb. 9:12; 9:14; 10:19; 13:20; 1 Pet. 1:2, 19).
[3] The statement by the Centurion must be understood in light of Jesus’ claim to be the Son of God (Matt. 27:40, 43). The ominous six hours of darkness (27:45), the tearing of the temple veil (27:51), and the earthquakes (27:51) at His death were divine attestation of the Father of Jesus’ divine sonship.
[4] Jesus’ miraculous works were given by the Father (John 5:20, 36; 10:25, 32, 38; 14:10, 11; 15:24; Acts 2:22) and enabled by the Holy Spirit (Matt. 12:28; Acts 10:38).