What does justification mean in the context of Christianity?

Justification is a major tenet of Reformed theology, explaining how believers are made right in the sight of God. It is not merely that God treats us as if we never sinned; rather, it means that, through Christ's sacrifice, we are genuinely regarded as having never sinned (1 John 3:5). The righteousness of Christ is imputed to us, making us acceptable before God. This is an act of God's grace, highlighting that our own works do not contribute to our justification—our standing before God is wholly reliant on Christ's completed work.