Everyone who practices sin also practices lawlessness; and sin is lawlessness. You know that He appeared in order to take away sins; and in Him there is no sin. No one who abides in Him sins; no one who sins has seen Him or knows Him.
Through Christian history some have held that all that is needed to constitute true religion is to embrace the doctrines of Christian orthodoxy, not expecting that people could truly become holy in this life. Therefore sin is permissible and expected, arguing that is was freedom in Christ. But God has given His Law to conform our conduct to His expectations, and whatever departs in any way from that Law is sin. The law determines what we should love or not love, when our passions should be restrained or indulged, our motives and aims in living, and how we should act toward God and toward people – loving God with all our being and our neighbors as ourselves. Whenever the requirements of the Law are not complied with, there is sin.
Christ saw sin to be so great an evil that he came into our world and gave himself to the bitter sorrows of death on the cross in order to redeem us from it, doing what the blood of bulls and goats, sacrifices and moral performances could never do. This should be a great deterrent from sinful living.
“Abide” (μένων menōn) also means to remain or continue. Usually the word was used to describe people permanently dwelling in a place. We are to dwell in Christ. I can’t help but think of the state of my home when I ignore it. The filth quickly accumulates. Likewise when I ignore prayer and Scripture the filth creeps into my life speck by speck until one day I am shocked by the stains on my heart.
“Anyone who continues to live in him will not sin. But anyone who keeps on sinning does not know him or understand who he is” (NLT). Matthew Henry wrote, “The sons of God know that their Lord is of purer eyes than to allow anything unholy and impure to dwell with him. It is the hope of hypocrites, not of the sons of God, that makes allowance for gratifying impure desires and lusts. May we be followers of him as his dear children, thus show our sense of his unspeakable mercy, and express that obedient, grateful, humble mind which becomes us.”