As the apostle begins unfolding the good news about the eternal life and fellowship that we have in God he begins with the nature of God himself: “God is light”. God himself is the light of all life (John 1:4) and all his deeds consist of goodness, righteousness, and truth (Ephesians 5:9); his light drives darkness out of the lives of all who follow him (John 8:12). God sheds the brightness of life into all creation. The life that he gives is wholly good, righteous, and true. His light delivers those who follow him from the grasp of darkness.
The very essence of God’s nature is opposed by three fundamental deceptions:
We confront the very essence of God’s nature when we claim to have his life while living in and practicing darkness.
We confront the very essence of God’s nature when we deny the existence of sin in us.
We confront the very essence of God’s nature when we deny the dimensions of sin in us.
These are the lies of darkness that oppose and confront the true nature of God himself. Their outworkings assault the holiness, love, mercy, and justice of God’s very nature while artificially exalting the depraved and unholy fallen nature of humanity to the place of divine dignity.
The very essence of God’s nature is manifest in us by two fundamental truths:
His nature is manifest in us when we walk in the light of his fellowship by the justification of his blood.
His nature is manifest in us when we confess our sins by the light of his sanctifying grace.
John’s first apostolic epistle unfolds itself from the glorious nature of God with clear affirmations of truth and concise denunciations of deception. The one who reclined with the Lord exalts him as the light of life and magnifies the justification of his blood and the sanctification of his grace as the means of true Christian fellowship.
Biblical Reasons 