1 John 5

The chapter moves from the internal evidence of the new birth (love and obedience) to the external evidence (the divine witness), establishing a firm foundation for the believer's confidence in life and prayer.

• He that hath the Son hath life (1 John 5:12)
• If we ask any thing according to his will, he heareth us (1 John 5:14)
• We know that we have the petitions that we desired of him (1 John 5:15)

• Keep yourselves from idols (1 John 5:21)

• He that believeth not God hath made him a liar (1 John 5:10)
• He that hath not the Son of God hath not life (1 John 5:12)
• There is a sin unto death: I do not say that he shall pray for it (1 John 5:16)

• The letter addresses early Gnostic or proto-Gnostic tendencies that sought to divide the humanity and divinity of Christ, hence the emphasis on the 'water and blood' (his baptism and his death).
• Believers were living in a culture saturated with pagan idol worship, making the final command to 'keep from idols' literal and urgent.

• The concept of 'victory' (níkē [G3529]) would have resonated with readers familiar with the athletic or military triumphs of the Greco-Roman world, here subverted to spiritual victory through faith.

• This is the conclusion of 1 John. It summarizes the previous discussions on the Spirit, the confession of Christ, and the nature of love.
• The structure functions as a pastoral wrap-up, shifting from doctrinal confirmation to the assurance of personal salvation.

• The reference to the 'Spirit, water, and blood' connects back to the Gospel of John, specifically the baptism of Jesus (water) and the crucifixion (blood/death), as the primary witnesses to His messianic identity.
• The 'sin unto death' likely alludes to the unforgivable sin or the 'sin leading to death' often associated in the New Testament with willful, persistent rejection of the Holy Spirit's witness (Mark 3:29).

• References to Jesus as 'the Son of God' connect explicitly to the testimony of the Father in the Synoptic Gospels (e.g., Matt 3:17).
• The command to 'keep' the commandments mirrors the teaching of Jesus in John 14:15.

• πιστεύω (pisteúō [G4100]): This is not mere intellectual agreement but active, trusting reliance upon the person of Christ.
• γεννάω (gennáō [G1080]): Used here to signify the divine act of regeneration; the 'new birth' is the foundational fact for the believer's character.
• τηρέω (tēréō [G5083]): More than just 'obey'; it implies 'guarding' or 'watching over' the command as a precious thing.

• The frequency of the phrase 'We know' (oīdamen) in the latter half of the chapter (vv13, 15, 18, 19, 20), indicating that the Christian faith provides cognitive certainty, not just emotional feeling.
• The abrupt shift from the high theological discussion of the Trinity and witness to the practical closing command regarding idols (v21).

• The identity of the 'sin unto death' (v16) remains a subject of extensive scholarly debate, with theories ranging from apostasy, to blasphemy against the Holy Spirit, to physical death as a judgment on believers for persistent sin.